How to Add multiple vendors to multiple legal entities in Dynamics 365?

In dynamics 365, you can copy vendor from legal entity to another by using the Add vendor to another legal entity form 

Go to Accounts payable / vendors / all vendor 


and select your vendor and click Add vendor to another legal entity


Note:: you must select vendors one by one (you can not add bulk vendors to another legal entity)

select the target legal entity


note:: you can not select more than one legal entity

click OK to confirm copy this vendor to the legal entity

you can see the created vendor as the below


But if you need to copy multiple vendors to multiple legal entities

you need to use Data Management functionality

use copy data into legal entity functionality


complete the required data and click copy into target entity


for more details, check this link

http://dynamics365ax2012.blogspot.com/2018/04/how-to-copy-legal-entity-configurations.html