Taking skirting boards off is often easier than going under floorboards. Depends on your wall finish but if you have just painted walls (or not wallpaper you might have to replace) then it’s an easy job to run cables behind. I’ve lived in a few properties over the years and found that the easiest way. There will be a gap at the bottom then just use no nails to put smiting back on. Even if it has to go through a doorway you can drill through the doorframe. Sounds excessive but it’s actually really simple.