My musical journey has been PA - piano - PA (but never both at the same time), and I would answer "no" to the question in the title, just from practical experience, with no elaborate theory behind it. Certainly it didn't work the other way around for me. That was my original thinking ("how hard can the piano be if I can already play the accordion"), and I was in for a surprise.
Of course, there are some skills (counting comes to mind) that are common to all instruments, so in that sense your practice time on the piano is not completely wasted even from the accordion's point of view, but that time would be much better spent practicing the accordion if that's your goal.