I got 99 problems but my WiFi ain't one

Right. Wifi, again.

https://imgur.com/a/xNCIx4j

This is my floorplan.

• red is where the only phone line in is (inside a mirror fronted cupboard)
  
• yellow is where the router was
  
• purple is where i moved the router too
  
• green is desk
  
  

moving the router to purple spot is great, i can work in the bedroom, on the terrace and at my desk with decent connection.

Im now likely to be WFH multiple days a week for.. possibly forever, and GF wont put up the current solution as it involves trailing ethernet across the wall, over the front door and the router is taped to a ceiling height window into its purple position.

Now I know its possible, what shall i buy that isnt invasive visibly? powerline adapters? multiple power socket wifi extenders? theres a at ground level where purple is, another one in the corner between purple and green, we currently have a wifi to ethernet adapter in the inner living room corner opposite green that connects the hifi to ethernet which mostly works