In your post you only listed main line games so I assumed that was what were we talking about here.
Final Fantasy 15 proper is not on Switch. Did you mean the mobile version?
1, 2, 3, 4, 5, 6, 11, 12, 13 Saga, 14, 15, 7R are all not on Switch. 12 surprising so. Thats just the mainline games. Point being that all things Final Fantasy are not switch bound.
The final fantasy games we've seen SE put on switch thus far were ports they could easily move over, which is fantastic. It doesn't imply in any way that SE would make a AAA FF game for the system.
Wait, 12 is on the switch isn't it?