Interestingly enough, Yuichi, while no longer at Konami, recently said some things on twitter that made it seem like Suikoden III on PS4 was more or less an impossibility but that the others are possible.
likely, never see Suikoden 3 outside of PS3 - unless there is a remake
-stupid middleware and contracts
Wonder what contracts would hinder S3 but not the others. S3 has no voice acting, I'd assume Konami owns the rights to Ai Wo Koete and the animation even if Gonzo did the actual animation.
Might be because it uses RenderWare as it's engine, I believe you can't get new contracts for that but old ones are upheld and RenderWare was in use on PS3 as well so that could be why the buck stops at PS3...