I'm using the new Geometry Script (https://docs.unrealengine.com/5.0/en-US/geometry-script-users-guide/) from Epic Games that was introduced in Unreal 5. The add-on enables all kinds of procedural stuff in real time. It's crazy! However still in beta. I faced some issues/bugs during development but managed to overcome them.
For the "3D textures" I did a little shader that samples the local position of the pixel in relation to the center of the rendered object and, with a little bit of vector math, I sample an inner fruit texture that I have for the inside. It's not perfect (it might give some repeating artifacts), but it works. So, for each fruit, I have a material for the "outer shell" and another one that I assign to the "procedural cut" for the inner part.
Here is how the inner texture looks with the expected "mapped mesh":
