My husband and I can’t play together

Interesting.  My buddy and I just played on two different PC's together at his home, earlier today.  Both his machines are Win11.  When I built the new machine for his bedroom, he left his old one in the living room, just for occasions like this.  So we can play BF6 together.  Both are on the same subnet, the old PC (8700K/3070TI) is hardwired, and his new PC (9950X3D/5070TI) is rocking an early WiFi 6 (802.11 AX router.)  Using a VPN is going to kill your husband's latency.  Just for giggles, I'd try sending one machine through WiFi.  It won't take but a few minutes to try...  In all my years in IT, I've seen MUCH stupider things work.  I can tell you without a doubt, that two machines on the same subnet can play together.

Reading again what KlootonicPlague wrote about NAT...  XB and PS might be using different ports, whereas Win PC's would be using the same NAT ports.  This would be a programming failure on EA's part.  I'm headed back to my buddies house this weekend, I'll head down to the basement where I store my 'magical box of cables' and find him an ethernet cable that will reach his room.  (It's a big box.)  Otherwise, I have a ton of cat-6E cable and can build him one.  This could be as simple as being on different subnets, and adding a route to (each others networks) on both machines?  I'd suspect this is EA's fault, for kissing the, I mean cozying up to console manufacturers, instead of the gamers who BUILT their company.  I'll post back with what I find this weekend.