Build work benches also build them in if you don't like looking at them

The only way i know of is with Mods,

There are some good mods for this, Valheim Plus is what I use, it increases the range of work benches and wards, with an individual setting for a wards spawn control radius.

Place more workbenches. The areas of effect have to overlap, so no uncovered milimeter is left. That way nothing can spawn in the covered area. You can build very big bases without anything spawning within them.