Thank you for posting this in Microsoft Q&A.
I understand you are trying to enable the "External collaboration settings" section, but you are getting error "This feature is unavailable or doesn't apply to the current tenant configuration".I'm sharing the screenshot to confirm that we have the same understanding.
Could you please confirm which tenant type you are currently using?
Based on the information provided, it appears you are utilizing an external tenant. The external collaboration settings feature is not available in external tenants, which is likely the reason you are encountering this message "This feature is unavailable or doesn't apply to the current tenant configuration".
Hope this helps. Do let us know if you any further queries.
Thanks,
Navya.
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