Have a look at the Bananapi options, especially the R3. (Or the R2, it’s a bit more mature)

It’s a very capable single board computer with onboard managed switch, including SFP cages. If you want, you can buy antennas and utilise the wifi 6, or get a dedicated access point.

PFsense, openwrt, et al all have images. I think some people also run the mikrotik OS on it. It’s powerful enough to run as a hypervisor so you can chop and change between all of these if you want.

It gets bonus points for accepting 5G modems for failover.