@Diego Pontes - Thanks for reaching out and Welcome to Microsoft Q&A platform.
It is technically possible, but we don't support all MCA to EA.
- Only customer led (same as web direct) to EA is possible via EA portal without changing the subscription tenant at the moment.
- And field led (enterprise MCA) to EA is only possible via support ticket and that should also be possible without changing subscription tenant.
Hope this helps.
If not, can you let us know what kind of MCA are you referring to?
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