Do they require live food? Can I just feed the adults crushed flakes, maybe bbs once in a while, what about frys are they big enough to eat crushed flakes or powder food?
I've had no problems at all feeding them. Firstly, they nibble algae and veggies. I'm not saying they're going to replace otos or SAEs, they aren't but they're omnivorous like all the common live bearers. I'm fairly sure they'll live off of flake, they eat it when I offer it. Just for absolute disclosure I feed a very varied diet of microworms, homemade food, mosquito larvae, seed shrimp, earthworm flakes, freeze dried daphnia and golden pearls, 100-200 and 500-800, plus some omega one flakes, so I can't say how they'd do on flake alone. Probably fine.
The same is true for the fry, I don't separate them, but they definitely eat some flake and I imagine they'll be fine on it.
Oh, they're beautiful!! (Not to mention I love all things mini) Would they get along with guppies or would guppies be too aggressive for their happy life?
I haven't kept them with guppies, but I have had them with some other fish and they seem ideal community fish. If you don't care so much about breeding them I'd even say they'd probably be fine with some German rams or swordtails.
It is possible they could hybridize with guppies, I can't speak to that with any authority, but bear it in mind.