How can I get a material to be the exact same scale on both static meshes and BSP meshes?

I’ve made some level architecture, castle walls to be exact, but some have detail on some segments that is too complex to be made in BSP, so I was wondering if I could have a tiling brick material that can be used on both the static and BSP meshes to maintain texture resolution, as custom textures on the static meshes vastly differ in quality compared to BSP. Yes, I’ve tried increasing texture size too.

You could use absworldposition (search for worldposition, the abs only returns the math operation) to set the tiling size of your materials which would simulate the projections that are applied to BSP surfaces. For example using an abswolrdposition node → component mask (R)(G) would created a planar projection for floors and ceilings. Run the component mask into a Divide node and divide by the amount of world space pixels you want your texture to tile across.
Mask (Y)(Z) if you want to tile across an X facing normal, and an (X)(Z) if you want to texture a Y facing normal. You should be able to find some tutorials now that you know the method to use.

[EDIT] Make the component mask a parameter so you can use instances for each different projection[/EDIT]