Don't Nintendo have a deal with Level 5 with this? I mean, Nintendo is the one publishing the games in NA and Europe, and considering it's a handheld series first and foremost, the jump to PS4 isn't probably of that much worth.
They have published Inazuma 11 as well. Ditto DQ games (from SE).
I think its somewhat surprising following Inazuma 11's move to multiple devices. But if they want to stick with Switch only then I am sure they have their reasons.