diff --git a/Source/Core/Core/IOS/USB/Bluetooth/BTReal.cpp b/Source/Core/Core/IOS/USB/Bluetooth/BTReal.cpp
index 244b2d4591..48bbe706c7 100644
--- a/Source/Core/Core/IOS/USB/Bluetooth/BTReal.cpp
+++ b/Source/Core/Core/IOS/USB/Bluetooth/BTReal.cpp
@@ -560,8 +560,8 @@ bool BluetoothReal::OpenDevice(libusb_device* device)
   const int ret = libusb_open(m_device, &m_handle);
   if (ret != 0)
   {
-    m_last_open_error = fmt::format(Common::GetStringT("Failed to open Bluetooth device: {}"),
-                                    libusb_error_name(ret));
+    m_last_open_error =
+        Common::FmtFormatT("Failed to open Bluetooth device: {0}", libusb_error_name(ret));
     return false;
   }
 
@@ -574,9 +574,8 @@ bool BluetoothReal::OpenDevice(libusb_device* device)
     result = libusb_detach_kernel_driver(m_handle, INTERFACE);
     if (result < 0 && result != LIBUSB_ERROR_NOT_FOUND && result != LIBUSB_ERROR_NOT_SUPPORTED)
     {
-      m_last_open_error =
-          fmt::format(Common::GetStringT("Failed to detach kernel driver for BT passthrough: {}"),
-                      libusb_error_name(result));
+      m_last_open_error = Common::FmtFormatT(
+          "Failed to detach kernel driver for BT passthrough: {0}", libusb_error_name(result));
       return false;
     }
   }
diff --git a/Source/Core/Core/NetPlayServer.cpp b/Source/Core/Core/NetPlayServer.cpp
index aac046ed44..7c0f18b68d 100644
--- a/Source/Core/Core/NetPlayServer.cpp
+++ b/Source/Core/Core/NetPlayServer.cpp
@@ -1071,8 +1071,7 @@ unsigned int NetPlayServer::OnData(sf::Packet& packet, Client& player)
 
     case SYNC_SAVE_DATA_FAILURE:
     {
-      m_dialog->AppendChat(
-          fmt::format(Common::GetStringT("{} failed to synchronize."), player.name));
+      m_dialog->AppendChat(Common::FmtFormatT("{0} failed to synchronize.", player.name));
       m_dialog->OnGameStartAborted();
       ChunkedDataAbort();
       m_start_pending = false;
@@ -1115,8 +1114,7 @@ unsigned int NetPlayServer::OnData(sf::Packet& packet, Client& player)
 
     case SYNC_CODES_FAILURE:
     {
-      m_dialog->AppendChat(
-          fmt::format(Common::GetStringT("{} failed to synchronize codes."), player.name));
+      m_dialog->AppendChat(Common::FmtFormatT("{0} failed to synchronize codes.", player.name));
       m_dialog->OnGameStartAborted();
       m_start_pending = false;
     }
diff --git a/Source/Core/DiscIO/CompressedBlob.cpp b/Source/Core/DiscIO/CompressedBlob.cpp
index 76b1366db0..35bbced94c 100644
--- a/Source/Core/DiscIO/CompressedBlob.cpp
+++ b/Source/Core/DiscIO/CompressedBlob.cpp
@@ -107,7 +107,8 @@ bool CompressedBlobReader::GetBlock(u64 block_num, u8* out_ptr)
   m_file.Seek(offset, SEEK_SET);
   if (!m_file.ReadBytes(m_zlib_buffer.data(), comp_block_size))
   {
-    PanicAlertFmtT("The disc image \"{}\" is truncated, some of the data is missing.", m_file_name);
+    PanicAlertFmtT("The disc image \"{0}\" is truncated, some of the data is missing.",
+                   m_file_name);
     m_file.Clear();
     return false;
   }
@@ -116,8 +117,8 @@ bool CompressedBlobReader::GetBlock(u64 block_num, u8* out_ptr)
   const u32 block_hash = Common::HashAdler32(m_zlib_buffer.data(), comp_block_size);
   if (block_hash != m_hashes[block_num])
   {
-    PanicAlertFmtT("The disc image \"{}\" is corrupt.\n"
-                   "Hash of block {} is {:08x} instead of {:08x}.",
+    PanicAlertFmtT("The disc image \"{0}\" is corrupt.\n"
+                   "Hash of block {1} is {2:08x} instead of {3:08x}.",
                    m_file_name, block_num, block_hash, m_hashes[block_num]);
   }
 
@@ -277,7 +278,7 @@ bool ConvertToGCZ(BlobReader* infile, const std::string& infile_path,
   if (!outfile)
   {
     PanicAlertFmtT(
-        "Failed to open the output file \"{}\".\n"
+        "Failed to open the output file \"{0}\".\n"
         "Check that you have permissions to write the target folder and that the media can "
         "be written.",
         outfile_path);
@@ -368,11 +369,11 @@ bool ConvertToGCZ(BlobReader* infile, const std::string& infile_path,
   }
 
   if (result == ConversionResultCode::ReadFailed)
-    PanicAlertFmtT("Failed to read from the input file \"{}\".", infile_path);
+    PanicAlertFmtT("Failed to read from the input file \"{0}\".", infile_path);
 
   if (result == ConversionResultCode::WriteFailed)
   {
-    PanicAlertFmtT("Failed to write the output file \"{}\".\n"
+    PanicAlertFmtT("Failed to write the output file \"{0}\".\n"
                    "Check that you have enough space available on the target drive.",
                    outfile_path);
   }
diff --git a/Source/Core/DiscIO/FileBlob.cpp b/Source/Core/DiscIO/FileBlob.cpp
index 13439d029b..b22bb6caa6 100644
--- a/Source/Core/DiscIO/FileBlob.cpp
+++ b/Source/Core/DiscIO/FileBlob.cpp
@@ -50,7 +50,7 @@ bool ConvertToPlain(BlobReader* infile, const std::string& infile_path,
   if (!outfile)
   {
     PanicAlertFmtT(
-        "Failed to open the output file \"{}\".\n"
+        "Failed to open the output file \"{0}\".\n"
         "Check that you have permissions to write the target folder and that the media can "
         "be written.",
         outfile_path);
@@ -90,13 +90,13 @@ bool ConvertToPlain(BlobReader* infile, const std::string& infile_path,
     const u64 sz = std::min(buffer_size, infile->GetDataSize() - inpos);
     if (!infile->Read(inpos, sz, buffer.data()))
     {
-      PanicAlertFmtT("Failed to read from the input file \"{}\".", infile_path);
+      PanicAlertFmtT("Failed to read from the input file \"{0}\".", infile_path);
       success = false;
       break;
     }
     if (!outfile.WriteBytes(buffer.data(), sz))
     {
-      PanicAlertFmtT("Failed to write the output file \"{}\".\n"
+      PanicAlertFmtT("Failed to write the output file \"{0}\".\n"
                      "Check that you have enough space available on the target drive.",
                      outfile_path);
       success = false;
diff --git a/Source/Core/DiscIO/NANDImporter.cpp b/Source/Core/DiscIO/NANDImporter.cpp
index d67bbf047d..aea5398426 100644
--- a/Source/Core/DiscIO/NANDImporter.cpp
+++ b/Source/Core/DiscIO/NANDImporter.cpp
@@ -272,6 +272,6 @@ void NANDImporter::ExportKeys(const std::string& nand_root)
   const std::string file_path = nand_root + "/keys.bin";
   File::IOFile file(file_path, "wb");
   if (!file.WriteBytes(m_nand_keys.data(), NAND_KEYS_SIZE))
-    PanicAlertFmtT("Unable to write to file {}", file_path);
+    PanicAlertFmtT("Unable to write to file {0}", file_path);
 }
 }  // namespace DiscIO
diff --git a/Source/Core/DiscIO/VolumeVerifier.cpp b/Source/Core/DiscIO/VolumeVerifier.cpp
index 860709448e..c1c9a8ae3b 100644
--- a/Source/Core/DiscIO/VolumeVerifier.cpp
+++ b/Source/Core/DiscIO/VolumeVerifier.cpp
@@ -312,11 +312,11 @@ std::vector<RedumpVerifier::PotentialMatch> RedumpVerifier::ScanDatfile(const st
     // so show a panic alert rather than just using ERROR_LOG
 
     // i18n: "Serial" refers to serial numbers, e.g. RVL-RSBE-USA
-    PanicAlertFmtT("Serial and/or version data is missing from {}\n"
-                   "Please append \"{}\" (without the quotes) to the datfile URL when downloading\n"
-                   "Example: {}",
-                   GetPathForSystem(system), "serial,version",
-                   "http://redump.org/datfile/gc/serial,version");
+    PanicAlertFmtT(
+        "Serial and/or version data is missing from {0}\n"
+        "Please append \"{1}\" (without the quotes) to the datfile URL when downloading\n"
+        "Example: {2}",
+        GetPathForSystem(system), "serial,version", "http://redump.org/datfile/gc/serial,version");
     m_result = {Status::Error, Common::GetStringT("Failed to parse Redump.org data")};
     return {};
   }
diff --git a/Source/Core/DiscIO/WIABlob.cpp b/Source/Core/DiscIO/WIABlob.cpp
index a8cce71cbe..6ffc8a286b 100644
--- a/Source/Core/DiscIO/WIABlob.cpp
+++ b/Source/Core/DiscIO/WIABlob.cpp
@@ -2033,7 +2033,7 @@ bool ConvertToWIAOrRVZ(BlobReader* infile, const std::string& infile_path,
   if (!outfile)
   {
     PanicAlertFmtT(
-        "Failed to open the output file \"{}\".\n"
+        "Failed to open the output file \"{0}\".\n"
         "Check that you have permissions to write the target folder and that the media can "
         "be written.",
         outfile_path);
@@ -2048,11 +2048,11 @@ bool ConvertToWIAOrRVZ(BlobReader* infile, const std::string& infile_path,
               chunk_size, callback);
 
   if (result == ConversionResultCode::ReadFailed)
-    PanicAlertFmtT("Failed to read from the input file \"{}\".", infile_path);
+    PanicAlertFmtT("Failed to read from the input file \"{0}\".", infile_path);
 
   if (result == ConversionResultCode::WriteFailed)
   {
-    PanicAlertFmtT("Failed to write the output file \"{}\".\n"
+    PanicAlertFmtT("Failed to write the output file \"{0}\".\n"
                    "Check that you have enough space available on the target drive.",
                    outfile_path);
   }
diff --git a/Source/Core/InputCommon/InputConfig.cpp b/Source/Core/InputCommon/InputConfig.cpp
index b531e56003..03d2874332 100644
--- a/Source/Core/InputCommon/InputConfig.cpp
+++ b/Source/Core/InputCommon/InputConfig.cpp
@@ -73,7 +73,7 @@ bool InputConfig::LoadConfig(bool isGC)
           if (profiles.empty())
           {
             // TODO: PanicAlert shouldn't be used for this.
-            PanicAlertFmtT("No profiles found for game setting '{}'", profile_setting);
+            PanicAlertFmtT("No profiles found for game setting '{0}'", profile_setting);
             continue;
           }