If users tracks are made in reaper in
any time signature they will automatically fit to any chord progression of any other DAW with the same time signature. Real time signatures fit real time signatures. If you have a recorded session in 12/8 then the 12/8 user tracks will fit that session whether they are wav, flac, mp3, wma... or midi.
In this day and age it's a normal thing that is expected.
So please don't shoot the messenger
