I mean, I could totally see Japanese companies looking to mostly western sales, especially if Nintendo didn't convince them that Switch would pick up where 3DS left off and run with it in Japan. PS niche in Japan and western PS/PC support seems like a very probable route for Japanese games that either are already niche or whose developers are sold on Japanese console industry fading into obscurity, even with portables.
Heck, plenty already do that, when 3DS is successful. Even DQ is hedging its bets and releasing multi platform with an eye on the west, instead of just hitting the biggest Japanese console its vision allowed as has been the norm. You also have Vita games going PS4 or PS4/PC and dropping vita versions.
But MH is of a bigger size in Japan than most games.
It would be strange, I think, if MH5 skips Switch or 3DS entirely. But it would be strange of the sort I could see Capcom doing if they really weren't sold on the Switch (yet) when they set about making MH5 and were sold on the limited future for domestic Japanese console market, but large western market presented by Sony. Sony throwing money in could really push this, but it's a bit of a stretch imo without Sony money. Sony did put money towards SF5, so maybe they did here too.
If Capcom has confidence that Switch can continue the console market in Japan and had it when they set to making MH5, I could also see MH5 being Switch exclusive. But I think it is likely that Capcom sees relative parity between the portable option and the stationary option (coupled with a chance to hedge their bets wrt the Japanese market) and decides to go multiplatform like Dragon Quest, only it being much more feasible to do so with PS4/Switch than PS4/3DS. Perhaps their working relationship with Nintendo/Nintendo money could convince them otherwise.
