Render mesh to texture without using scene capture 2D

I need to render a flat 2D mesh which uses x and z coordinates repeatedly to a texture for a 2D game’s shadow mask.

This works fine with scene capture 2D but it quickly becomes a bottleneck. I have previously used this technique in Unity and was able to render 30+ to a texture in under 1ms.

The same task here takes over 30ms.

So I’m looking to just render a plain flat mesh to a render target quickly. The mesh does need to use a material for the WPO offsets it requires.

Some properties that could make it easier:

2D coordinates, flat or ortho rendering, no need for any depth in the mesh, triangles are fine but they must be with a material.

I am considering using a canvas with Draw Material Triangles but its a real pain.

Trying to keep it a strictly BP project if I can!

Anyone out there want to think about this problem, or suggest workarounds to avoid SceneCapture2D?