To open AVCHD .mts files in Windows 11, you can either recode the files or install AC-3 codec in Windows
To recode the files, you can use ffmbc softweare from click here
To strip the audio track, do the following or similar command for fmbc
ffmbc -i "00003.MTS" -vcodec copy -an -f mpegts "00003.new.mts"
this command will remove the audio track all together. MTS files without audio open just fine.
For bulk converting of multiple files, you can also automate the above with a .bat file like so
for %%a in ("*.mts") do ffmbc -i "%%a" -vcodec copy -an -f mpegts "%%~na.new.mts"
Do not forget that .mts and .MTS are treated differently!
If you want to keep the audio, you may use a converter like Avidmux to convert AC3 track to AAC track. You can get it click here
To install AC3 codec that has been removed from Windows, use the utility from click here