I’m not so sure about egui being next gen really. It seems more like a limited version of Dear ImGUI written in Rust, with the fact that it is written in Rust as the main selling point, not so much that it is better than ImGUI:
But anyways, if you want to use egui in Defold as an extension you need to compile it into libs for each platform you wish to support. We do not support wasm libs.