If I have a single US region A board and a Asian region B board, could I just desolder the connectors on the B board with a desoldering gun and swap them out with a US connector?
Technically, yes. But that's gonna take a ton of desoldering, which is gonna put a lot of stress on the PCB itself. It sounds immensely tedious, just get another A board of the appropriate region and keep the other as a spare