As a terrible keyboardist, I can say this is a bit of a mystery to me. I have played guitar and other string instruments for about 35 years, so in a general sense I think there’s a couple of phases of learning things like this:
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get the physical dexterity and control to make your fingers do what you want, like what white noise and morphic mentioned
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get used to the shapes until they’re muscle memory…that’s the practice, practice, practice bit
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tie those shapes to the progressions you want, and use your newfound abilities for good
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learn to transpose those progressions into the correct key (and thus chord shape) on the fly as you play
Ironically, I can do the last two pretty well because I can do it on guitar and notes are notes, but I never learned to do the first two very well, so it all comes out sounding like unadulterated shit anyway.
Were it me, I’d start with the scales you favor and play around with all the chords you can find that support those scales. That’d likely give you a wider variety of chord shapes under your belt as well as being able to support the keys you’re likely to be composing in.
