There is some tooling for "editing" Gaussian Splats. With GaussianSplatRenderer object selected, the inspector shows options to manually edit the splats, as well as create "cutout" objects. If you ...
SIGGRAPH 2023 had a paper "3D Gaussian Splatting for Real-Time Radiance Field Rendering" by Kerbl, Kopanas, Leimkühler, Drettakis that is really cool! Check out their website, source code repository, ...