Recommendations for new hardware supporting many multiple BSS (multi_ap)

[Serafean]

Hi,

I've been running an AP off the venerable rt2800usb driver for more than a decade, and the device has this speciality:

        valid interface combinations:
                 * #{ AP, mesh point } <= 8,
                   total <= 8, #channels <= 1

which I've used to run 5 different networks from the single dongle. Searching through new chips, I can only find support for at best 2 separate BSSes.
I'd like to add 5ghz support. Currently I have one BSS also on 5ghz using an AWUS036AXML, but bringing the others into this decade would be nice too, without 1 device per BSS.

Any hardware recommendations for this fun usecase?