Thanks DaSalo,
It's not working like that.
The new part that I created is machined part, made with Boolean operations, so I have more parts bodies inside , which is an assembly.
When I copy/paste, I get everything mixed up, all the sketched I have to reposition and I have a lot of conflicts...
I need some advices…
I changed some parts, the old ones were symmetrical, but I created another parts by scratch and now I have a conflict with UUID so I need to use the .catproduct from the old part (with the correct UUID) with the new geometry created by me.
I know that I cannot access UUID...