I just tried it and it works as expected for Windows <--> Android.
I was using syncthing but this will replace it for one offs.
EDIT: I checked out another app in the comments and their website mentioned that it didn't work with a VPN. I can also confirm that LocalSend works when connected to VPN.
I know that Meta and Google make money from data, but they are also competent, so they can be trusted to at least not get breeched or sell the data to the an aggregator.
If the choice was between 'the competent concentration camp' and 'the concentration camp run by one dude in his spare time', then if the question is 'which one is more likely to feed me', then yes, that is apt.
I was using syncthing but this will replace it for one offs.
EDIT: I checked out another app in the comments and their website mentioned that it didn't work with a VPN. I can also confirm that LocalSend works when connected to VPN.