I don't have any kind of socket for LQFP-100 that could be used for programming chips, even if I had loose chips (well I could get loose chips for course). I suppose sockets do exist??
Programming them on the board then removing them is not impossible but renders the rest of the board useless and the removal procedure itself involves a lot of heat, I wouldn't really be confident of not damaging the chips during removal and once removed, there'd be no way to test them.?
In any case I think the capability to remove and replace STM32F446 chips successfully would be beyond 98-99% of constructors.?