If all you want is "send and receive files across a local network" then I can recommend Magic Wormhole and Magic Wormhole William (depending on which app store you use; e.g. Google Play Store, F-Droid, Homebrew, Debian/Ubuntu APT repos, etc). It will attempt to use LAN if it can and uses PAKE for auth.
I'm using primarily the "remote" aspects of it, so not surprised to hear that.