ODM AD does not parse multi-string attributes like proxyAddresses to manipulate specific entries like an SMTP address or remove a particular domain. It can not be configured to not add the source email address as a target proxyAddress.
When running a Workflow to Stage the data, it will use the selected Template using the default mapping section for proxyAddresses. It will add the source LegacyExchangeDN (LEDN) attribute as x500 entry on the target.
Template Mapping
Value: GetProxyAddresses(S.proxyAddresses, T.proxyAddresses, prefix(Result("mail"), "SMTP:"), prefix(legacyExchangeDN, "x500:"), prefix(Result("legacyExchangeDN"), "x500:"))
Post migration PowerShell scripts can be run or added to the Workflows to clean up or remove any unwanted domains listed in the copied objects.
