As a personal knowledge system, the vault on android MUST stay with me 24hrx7.
A good way to access from windows (except thru $$ obsidian sync), i guess is directly sharing as samba server to windows. This is not easy, need a paid app called “lan drive” and a paid .exe called “multi port forwarder”. I also recently bought a ethernet cable card for android phone. the speed is around 8-12MB/s, not slow i think for text files sharing.
HOWEVER, the loading of the vault took about 5mins+, from windows loading android vault thru the LAN cable.
It’s worse (over 15mins) if using wifi.
I got another vault that put study material as this may not need to be 24hx7 ready.
You’ve got options other than Obsidian sync, such as using Dropbox or similar. Some of them do require another sync option, but they can be made to work. See Sync your notes across devices - Obsidian Help
To access your vault through a samba share and cellular data service, seems just painful and not worth the effort. Using LAN cable, then where’s the benefit of using your android device?