Angelfish in a 20 gallon?

I tried to ask this question before, but I think it may have been too lengthy so I will try again.

I have a twenty gallon that currently houses two female betta, three platys, and a guppy-- all of which will be moved to a 20 gallon long very soon.

I have a 55 gallon with a BGK and three angelfish. Someday soon, I will be moving all of these fish to a 150 gallon, along with blue rams and hopefully a couple more angelfish.

I don't want to add anymore fish to the 55 gallon, but I would like to get the angelfish I will be putting in the 150 gallon sooner than later, so they will be the same size when introduced to each other.

Can one or two angelfish live happily in a 20 gallon regular aquarium with two or three blue rams? And if I were to get them, they'd probably live with the betta, platys, and guppy at least for a few days or weeks, would that be okay?