Can you create an SQL SERVER 2016 distributer that merges data between a 2008 R2 server to another 2008 R2 server?
Yes.
This is covered in Using Multiple Versions of SQL Server in a Replication Topology:
For all types of replication, the Distributor version must be no earlier than the Publisher version. (Frequently, the Distributor is the same instance as the Publisher.)
Since your Distributor version is a later version than your Publisher version, you are good here.