Can the Wavlink or Win-Star WN579X3 or WN579G3 (AKA Persevere, Net-DYN) be supported?

According to ShoutWiki these cheap 64MB/8MB direct-plug 2x2:2 AC devices has a MT7620A (Processor and 2.4GHz radio), RTL8211F switch, and a MT7612EN 5GHz radio.

It's coverage is good on both bands thanks to internal amplifiers, however the M79G3.V5030.180719 firmware is crappy (tends to use 40MHz unless you unselect short GI, don't assign DNS on the DHCP ack, etc.).

The OEM reveals a little bit of the internals on this video. On the other hand this Russian forum discussed about the internals and firmware/updates. And this PDF has some internal pictures and models/variants comparison.

Maybe the Net-DYN above mentioned firmware is for the Win-Star G3 variant.

Could the X3 or G3 be supported?.

Mediatek mt7620a is fully supported. So it may be easy to build image for your device.
Start with:
https://openwrt.org/docs/guide-developer/add.new.device
https://openwrt.org/docs/guide-developer/adding_new_device