I am aware of the problem, but unable to figure out what is wrong. I can't run WPA3 here, so there's not much I can do.
There's a new version of wolfssl out. I'm currently testing it then I'll send an update patch to openwrt-devel. Here's the patch for it if you want to give it a try:
Mesh-Auth fails on openwrt-19.07.0-rc2 with wolfssl
I have TP-LINK TL-WA860RE on OpenWrt-Tiny 18.06.5, r7897-9d401013fc with libwolfssl_3.15.3 which works out of the box with 802.11s. So i don't know if wolfssl is the problem here.
The other box in this setup has openwrt-19.07.0-rc2 with wpad-openssl.
This didn't work for me. I got the following error: that file is already provided by package * libubox 20170601* opkg_install_cmd: Cannot install package wpad-openssl on both my devices running 19.07:
-TP-Link TL-WDR3500 v1
I used opkg install libubox20191228 libubus20191227 --force-overwrite then
opkg update && opkg remove wpad-basic && opkg install wpad-openssl and it installed with no issues.
...compiling with hostapd-wolfssl full running on an AP (UniFi AC LR ath79 k5.4) set to use SAE-only (WPA3) and now I have no problem getting or staying connected. Previously this was most definitely not the case.