Modelling in joints (express joints, tile joints, joinery joints)

[Shpox]

Hello all,
Just wondering if I can pick your brain on modelling in joints that separate geometry.
I generally use textures for this purpose, but for certain cases I need to model in a joint, often for rendering purposes.

Common examples are modelling in the joint between lines of cabinetry, mirrors or tiles in very specific scenarios.

I often use TIG's offset, adjust the offset, and hopefully use Push Pull to pull this off, but it can be very ardous.

Is there a plugin that will let me do this? Perhaps a plugin that can do an offset not of all boundaries, but rather selected ones. I don't mind doing the extruding with Push Pull, but often it's drawing in the joint from the centreline that can be time consuming.