I was looking to ask for this too, and actually decide to create a plugin with a little help from a famous AI...
We came up with this :
https://github.com/didli/xed-copy-path-plugin

• note 1 : this was done for my sole purpose, I'm just sharing it for anyone interested
• note 2 : I preopen xed with some default files, I had to restart xed again once the plugin is enabled to see the entry menu in any files opened
• note 3 : my 1st intent was to right-click a tab to copy the path, but I couldn't get this to work, so I intentionaly put the entry-menu in the right-click context menu (inside the file content)