Workforce Identity Cloud (WIC) does not currently support Inbound SCIM where third-party apps trigger the SCIM endpoint to provision users/groups to Okta.

• Workforce Identity Cloud (WIC)
• SCIM
• Provisioning to Okta 
• User Lifecycle Management

Currently, Okta supports provisioning users out to third-party apps using SCIM but does not support inbound SCIM provisioning.

• Utilize any Okta Integration Network (OIN) app that supports provisioning To Okta. An inbound User source is generally referred to as a "Profile Source" or "Source of Truth" and works through Okta's import process.
• An alternative to SCIM and imports for User provisioning inbound to Okta is Anything-as-a-Source (XaaS).

Related References

• About Profile sourcing
• Build an Anything-as-a-Source custom client integration
• Okta and SCIM Version 2.0 describe the SCIM endpoints that Okta uses to provision users/groups to third-party apps.