These devices are home-polling, which means commands/info is managed through WAN and their home servers.
Even if you don’t use their app, it still uses their servers.
FWIW, i also use home assistant. But some of the devices I have were not choices I made, so it’s a slow trudge replacing them all with locally-managed devices.
I highly recommend this one.
If all you’re looking for is a way to send files from your phone to your server, this is the simplest way to do it.
Share your server volume as a SMB, mount to phone via Material Files.