Hi @Nick Hey,
Thank you for posting in this community.
Your question is whether it is possible to access SharePoint sites not using credentials but using IP addresses? Please correct me if I am wrong.
If I understand correctly then I am sorry to say that we cannot access SharePoint Site without credentials relying only on IP address.
Security is very important for SharePoint and SharePoint requires credentials to verify that the current user has permission to access certain content or to modify, delete, etc. This is the way SharePoint is designed and there is no way we can change it.
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