Shared Mailbox with Different Domain

Hello!
I have a question about a shared mailbox and its domain. 
Currently, I have an outlook mailbox shared with my colleagues like info@aaa.nl.
And my colleagues' e-mail addresses are, for instance,11111@aaa.nl, 22222@aaa.nl, 33333@aaa.nl.

Question 
Is it possible to add 00000@bbb.nl to our shared mailbox if 00000@bbb.nl is the outlook email? 
If possible, does anyone know how to add? 

Thanks