I wouldnt do it without a login even on a LAN

I see what you mean. It’s 1 year that I’m not checking my minecraft account but I don’t think I have ever had to create a microsoft account

Elaborate more on the first point please. I know and use opnsense but what about the VPN?

Why did you killed Minecraft after MS takeover? Especially after you wrote that you use gmail

On my little server i have:

2 pihole VM for DNS and redundancy 1 opnsense router VM 1 owncloud VM