Replace the MacBook Pro 2019 keyboard

I would strongly recommend you rethink your direction here!

Apple offers an extended warranty program for butterfly keyboard failures. If you have a bad key or multiple keys Apple will either fix the single key of replace the entire uppercase with a new keyboard.

Replacing a keyboard is quite an intensive a project! In Apples wisdom they rivet the keyboard in! So you’ll need to drill out the rivets without damaging the uppercase, Then you have the next problem which is finding the 4 Generation keyboard which is what your system had.

In the end you’ll spend a lot of time and the results won’t be as good as what Apple’s uppercase rebuilders can achieve with custom tools and lots of experience! If they mess up it goes into a trash bin and move on, what are you going to do if you mess up?