Instead of range extender, why not use power line Ethernet like this for example:

https://www.lazada.com.my/products/tp-link-...5&utm_campaign=[SSA-020000000000-00000-00000-0]:%20Top%20Computers%20and%20Laptops&utm_term=[SSA-020700000000-00000-00000-0]:%20Top%20Network%20Components_xxmo0000000at0207_c_aud-315154827062:pla-451446129733&adjust_tracker=t2v78t_5n20iw&adjust_campaign=1415046120&adjust_adgroup=55351296413_c_aud-315154827062:pla-451446129733&adjust_creative=451446129733_207251_118086785&tracker_limit=1000000&ef_id=WzBT4QAABf-Rk6Qq:20180625023057:s

Now you get the Ethernet direct from Ethernet port at router which is faster than WiFi theoretically. Note that WiFi is not full duplex like LAN. It is only half-duplex

The problem with mesh that is using wireless as backbone. How to expect maximum throughput if the connection to other unit is lower due to weak signal? No, it cannot. The only way is to connect using cable. The problem with Lyra connected through Ethernet cable is that if there is power supply interruption, the units cannot re-sync themselves because sync can only work through wireless. You need to unplug cable, let it sync and then re-plug cable . A bit flaw there

Why need long cable?

The concept is like this. You pulg the PowerLine Adapter to 3-pin socket near your Wi-Fi router. Then connect LAN cable from router to the PowerLine adapter. In your bedroom, You connect the PowerLine adapter pair and then sync it with the adapter at the router. The Internet is using your AC power line for transmission. Then you can connect your LAN cable to the adapter in your room.

Say you don't want cable to PC or laptop. You can use an adapter with built in router. Something like this.

https://www.tp-link.com/my/products/details...PA8630-KIT.html

It can also be PowerLine extender, but using LAN to extend from router instead of extending from WiFi side which will affect latency/speed. You can also use spare WiFi router in bedroom if you have any to combine with your regular PowerLine adapter

Wireless backbone downside is the same but the sync problem with Lyra is what I knew from other user. I'll just stick with Asus router that support AiMesh. It is more flexible and I can add whenever I wanted.