In my network with a dedicated router (& firewall) PC, a few switches and a total of 45 PC's (Linux, Windows and FreeBSD, 70% is bare metal, the remainder is virtual) there is no problem hooking up PC's for LAN gaming. or anything else for that matter.
Was it an old(er) game that you were using for the LAN gaming? I remember old(er) games having options for LAN gaming, using a serial connection, by using IPX/SPX and also the TCP/IP protocol. There are ways to transfer IPX traffic over the TCP/IP protocol, but that is all from yesteryear. Still, by using HomeGroup, you might have enabled the IPX traffic to travel over TCP/IP. On the other hand, new(er) games only use TCP/IP anymore.
Homegroup has always been disabled in my network, Onedrive file sharing implies the cloud, which for most is not their own LAN, which makes it practically forbidden in my network. Windows (10) file sharing wizards aren't needed or used either. Linux PCs communicate just fine using Samba. Network printing and scanning, it all working pretty much out of the box. Are you sure your network is configured ok? No double NAT
going on anywhere?
To do networking well, it requires a fair amount of studying. It is an interesting field in the world of computing and if you choose to become a network specialist, you can (usually) make very nice sums of money.
Be that as it may, most people can't or won't spent time on networking basics and rely on wizards and automated systems like HomeGroup to do the work for them. It is my personal (and perhaps not so humble) opinion that you shouldn't rely on these automatic systems and figure it out for yourself. Yes, it is a headache in the short run, but you'll benefit from it later.