Yes, the bolt pattern fits. However, they may not be the exact same length and position as the stock mirrors.
A common thing to do has been get a longer set of early-generation Yamaha FZ-1 mirrors and bolt those on. They're like Gen 1 mirrors but noticeably longer.
Nope. Since he didn't specify, I am assuming he was asking about putting Gen I FJR mirrors on an 2017. They would offer no additional benefit and be butt-ass ugly at the same time.