@Info Technically you can. As Azure AD b2c allows any service to be the IDP which can work on OAuth 1.0, OAuth 2.0, OpenID Connect, and SAML protocols. There is however no step by step document from our side.
But feel free to take reference from other IDP documents mentioned here : https://learn.microsoft.com/en-us/azure/active-directory-b2c/add-identity-provider to get the idea.
Also check with OneLogin if they already have a dedicated steps for this.
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