Hi @Jeremie GLAIS ,
Thank you for posting in this community.
Here are steps to allow someone other than the site owner to edit the list of shared access permissions.
1.In the "Intranet" main site, Settings->Site Permissions
2.Change how members can share
3.Depending on your needs, choose the first or second option(You should now be the third option.).
Hope the information can help you. And if there have any unclear or misunderstanding, please feel free to post back and we’ll continue to help you all the time!
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