You can't take sims from the sim bin of one 'hood and find them in another unless the 'hoods are connected by being a shopping district, downtown, etc.
The wrong way to move from one of the primary 'hoods to another would be to move the residential lot they are on to the lot bin. That is available in all 'hoods. But it causes problems with memories and the like, eventually leading to bugged lots or worse.
The right way to move a sim is to package the lot with them on it, exit the game, install the lot, then enter the 'hood you want them in and place the lot.
Thank you soo much!
I'll do that!