Thanks Paul !
Yes, it still requires a little calculation: dividing handle[0:11] by 10000.
This SuperTool script allow you to retrieve any object creation date (don’t care about people category warning):
[Gramps SuperTool script file]
version=1
[title]
SuperTool - Object Creation Date
[category]
People
[initial_statements]
from datetime import date as dt
[statements]
hand: float = float.fromhex(obj.handle[0:11])
creation = dt.fromtimestamp(hand/10000)
[filter]
[expressions]
creation
[scope]
selected
[unwind_lists]
False
[commit_changes]
False
[summary_only]
False