I wanted a router and range extender that would work together as a mesh.

Two things I wanted to accomplish:

   1) Wired mode (Access Point) for the extender

   2) Wi-Fi 6 network throught the house and yard

I purchased an AXE5400 router and RE615X (AX1800) range extender (Hardware 1.6), and have them both working as a Mesh with the latest firmware on both.

Disappointing things I discovered that are not discussed in the advertising or web pages:

1) I ran an ethernet line out to where I wanted the extender.
    It was only then that I discovered that it can't work as a Mesh in Access Point mode.

    I had to bring it in a lot closer so it would work in wi-fi mode as a Mesh extender.

2) I got it all set up, and then didn't see wi-fi 6 in the Tether app.  

     After more investigation, I found out that in Mesh mode, it only works in wi-fi 2.4 and 5, not 6.

These are two of the main reasons that I purchased this combination of TP-Link products, so they would work together as a pair in a mesh network.

Both of these features are heavily advertised, but not the limitations that I described above.

I'm just frustrated that the extender doesn't work with all the advertised features in Mesh mode!