Hi @Pröbstle, Cornelia ,
Thank you for posting this community.
For your questions:
1.The “grant permissions” page can only be accessed by users with full control permissions, but not by users with other permissions levels.
So, there is no way to allow the user to share with 'edit without delete' permission level, unless that user has full control rights.
2."Site owners and members, and people with Edit permissions can share files and folders, but only site owners can share the site.": Only “Site owners”, “Site members”, and “Edit” permission can be granted without the site owner's acceptance. For example, even if a user has “Design” permission, which is higher than “Edit” permission, there is no way to share files without the site owner's acceptance. This is by design.
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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