I found a solution. I've sold all tplink routers (with some losses) and bought asus. Asus works flawlessly and able to build mesh any router to any with roaming and even wired backhaul. I have ax86...

@Kevin_Z What is the current status of this issue? What did your developers answer?

Same story.. Bought ax90 and ax73 for big flat covering and replacing xiaomi routers. Was surprised that it's possible to use ax90 as main router and ax73 as an wired access point, but not in mesh...