I had to overwrite /lib/firmware/regulatory.db and /lib/firmware/regulatory.db.p7s with the file which comes from FriendlyWrt 20231223 (I attached in this article). This procedure is no longer required on FriendlyWrt-24.10-20250228, NanoPi Zero2. MT7921 works as 802.11ax 5GHz AP after setting count...