heya robertkoss, FusionAuth is software you can run yourself for free which is comparable to Auth0, Clerk, WorkOS. We have a community plan with unlimited SSO providers (SAML and OIDC; sorry, we don't support WS-Fed).
Here's the doc to set up an OIDC provider to Entra ID: https://fusionauth.io/docs/lifecycle/authenticate-users/iden...
We have other things we charge for (pricing here: https://fusionauth.io/pricing?step=plan ) but we don't charge per SSO connection.