egui_dnd
... is a drag & drop library for egui.
Give it a try here: https://lucasmerlin.github.io/egui_dnd/
To get started, take a look at the simple example.
Demo Video:
https://github.com/lucasmerlin/egui_dnd/assets/8009393/a05fa961-ef12-479c-a3fd-f765160e048e