Editing the Crease of a Polygon.

When working with quads, there’s always going to be a crease or virtual edge that’s created between diagonal vertices.

For something that I’m working on, in edit mode the “crease” is between the two vertices that I want, but when switching to object mode, it changes. This is causing it to clip into another object. Is there any way to manually edit this? Thanks in advance.

The only sure way is to split the face on the diagonal you need.

If you need only quads, you can try and move some vertices a little (if you can, of course), so that the splitting edge can switch, maybe…

The Richard’s answer is the only sure.