Wall-mounted fixtures are popular in some contemporary style homes. They present the problem of splashing water onto the wallpaper . The are tricky to cut around when hanging the paper. If possible and in the budget, it’s best to have a plumber come remove the fixtures. If the faucet cannot be removed, then I will have to make a lot of “relief cuts” in order to work the paper around the obstacles. Then very careful and precise trimming with a sharp blade around the escutcheons (wall plates) of the fixtures. These cuts do present more openings that splashed water can wick into, which could lead to curled seams. Done!