According to the French website Factor News, a number of facts have arisen about AnyArts, the development team behind Seasons of Heaven. The biggest piece of information being that the team doesn't even have a Nintendo Switch devkit. They've been developing on a PC the whole time.
Developing on a PC is nothing new for console games, but Nintendo consoles are usually developed on their respective console's development kits due to their fairly different architecture. Not only this, but the Nintendo Switch is new, not even released to the public yet. Developing a game for a brand new console that works very differently than others should probably warrant developing on said console.
This isn't to say that Seasons of Heaven is going to be a flop, but this news is also coupled with the fact that AnyArts pitched the game to Nint endo once before and was rejected, and that they admittedly do not have any development space according to their founder.
This wouldn't be surprising if it were a PC release. The PC indie world is a much bigger wild west, but being an exclusive on a console that, yet again, has yet to be released, isn't really a good sign. It's also worth mentioning that Nintendo-proper hasn't made any sort of press release about the game either.
Hopefully, this news isn't as bad as it seems because the trailer and the screenshots look beautiful and the premise sounds very heartwarming.