master-r13325-289c632425-20200521-ath10k-test
It is possible that the old mainline ath10k is usable again. I haven't tested it much yet, but at least no crash materialised quickly.
OpenWrt's wifi driver mac80211 was updated today to version equivalent of kernel 5.7-rc3 wifi, and the SWBA overrun errors seem gone at the first glance.
Relevant discussion also in the exploration thread a few weeks ago:
Netgear R7800 exploration (IPQ8065, QCA9984)