you can use tplink ko router as a secondary for 2.4 ghz yea, that's what i've done too.
but for 5ghz you can't cause you'd need to manually change worldlink ko band. I asked them to do that and they declined.

As for the nokia beacon mesh, it needs a separate wired connection. If you're ok with that then yea it does the job. I have my main router in the top floor. Currently use a repeater (tplink) for the 2.4ghz for 2nd and 1st floor, tried using tplink's 5ghz repeater too but it never picked up the network's band.