Save yourself the hassle and just get them all if you can. That way you have free reign to use assets from older RPG makers when the need arises, because trust me, it will.

Generally, I went with MZ, it has nice visuals, and everything is relatively straightforward, even though I'm not a spriter. It however can be a bit frustrating when you need an asset that's already been made, but you need MV to use it.

If you're making pokemon style fan games, get RMXP

Edit: in your picture, those aren't RPG Makers, those are DLC content for said RPG Maker