You are right, the Common module doesn't have the same email builder, which is odd. What you can do instead is pass the value being checked an input to the common module.
Eg:
If in the email builder you wanted something like:

Click the expression tab and we can see that is the same as:
If(IsSet(EmailAddressDomainPart(Email.Message.from)), Contains(EmailAddressDomainPart(Email.Message.from), "@BadDomain.com"), false)
So you can always create a string variable like EmailAddressDomainPart(Email.Message.from)

Then in the common module have an input string setup like so: (highly recommend you set a default value for edge cases)


Then just do a standard decision action with, Contains(Task.FromAddress, "@BadDomain") for example and away you go, or use a datatable lookup etc.
In the inbound flow when you call the the common module you will have that input

Let me know if you need any further guidance with it.
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Anton Vroon
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