Hello @Robin H
Yes, you would need to first convert the domain to standard using Convert-MsolDomainToStandard cmdlet for managed authentication. Make sure you specify -SkipUserConversion:$true with Convert-MsolDomainToStandard cmd as you will be converting the domain to federated again. Then convert the domain back to federated again using Convert-MsolDomainToFederated cmdlet as the relying party needs to be created on your new ADFS Setup.
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