I already have a router with no wifi capability working perfectly. Would like to purchase an AP that supports WIFI6 and WPA3, and is, of course, OpenWrt friendly.
Any recommendation?
I couldn't find one in the pinned topic, which mostly consists of wireless routers.
None of OpenWRT-supported APs are WiFi6-compatible.
WPA3 is supposed to be hardware-independent, but at least one WiFi chipset manufacturer (Marvell) messed things up so that it won't and can't work with the available driver. So avoid Linksys WRT1200, 1900, 3200 and 32X, and you will likely have WPA3.
Any with Qualcomm wireless chips and enough CPU power. Then, the primary factors are local availability, wife acceptance factor, and whether you would accept something which is supported only in OpenWRT snapshot.
For WiFi5, I use a Ubiquiti AP-AC-PRO. QCA988X based, AC Wave 1. Be advised that it is only powered by 48V PoE (passive or 802.3af/at). I run one here with firmware built off master, replacing the CT driver with the QCA driver.
Weekdays there are usually 12 active clients connected at all times. On the weekends there can be 20+ clients connected across both radios and it runs flawlessly. The 5GHz radio is set to use WPA3 only, while the 2.4GHz radio does WPA2 for older devices that don't support WPA3.
I also have a Ubiquiti nanoHD (802.11ac Wave 2) that I bought to eventually the AP-AC-PRO. The Mediatek wireless driver still needs more work, but @nbd has been making constant progress on it.
You do realize that the AP-AC-PRO is Wi-Fi 5 pre-wave-2 only. Years ago I did also use it and it performs well but nowadays it's quite dated. I, meanwhile, upgraded to MR33 which are indeed Wi-Fi 5 wave-2 and perform equally rock solid. The only trick with those is that you need some luck to get one with an older U-Boot version which allows easy OpenWrt installation.