Wallpapering question

Hi all, I am stripping one wall of wood chip in my sons room to put a feature wallpaper up. If I had the time I would take it all off but for now the remaining wood chip is just getting a couple of coats of paint...my question is where the papers meet in the corners I’m concerned it looking rough ..any ideas ? Caulk ? I intend to score it with a Stanley down the corners to make it as neat as poss before I strip it off. Cheers

Yes, to botch it, do it the way you suggest. To do it correctly and to get the correct result, remove all the woodchip and prep the walls.

Cheers