@Beaver @openstreetmap_ca

I think the quickest way is with JOSM + the Building Tools plugin. If the buildings are all rectangles or “L” shaped then the Mapathoner plugin is really quick too.

Building tools is quick enough that if I’m fixing an area that’s been mapped wonky it’s often a lot quicker to re-trace the skewed buildings in a fresh layer and use the Conflate plugin to merge them back into the main layer than it is to fix the geometry directly (and that include individual checks).