How to keep 2 different instruments in sync ?

Hi everyone,
Imagine you have print parts for 2 instruments with different concert key but same "content".
For example: You have one trombone player in C bass clef, and one Euphonium in Bb / treble clef.

My current way of working:
Finish the complete piece with one of both instruments, and before printing parts, I add the 2nd part, copy everything there and musescore will transpose everything,...
That does work...

BUT:

The next time, I change something in the trombone part, I have to change it manually in the Euphonium part, too.
Is there a way to have 2 different instruments in sync somehow ?

Thank you
Uli