Relating nodes between 2 independent databases

Good morning,

We are using a neo4j database for tracking samples we process in our labs. We now plan a cooperation with another lab which uses their own neo4j database.
Is there a way I can establish relationships between nodes in "our" database and "theirs"?

Our database contains all the samples that are beeing processed together with our process-templates for our processing tools. The other lab also has a database that contains process-templates for their processing tools.

If a sample is processed in our lab we relate the sample to the process-templates of the processing tools that are being used. In order to maintain "data coherence" I would like to do the same with processes that are executed in the external lab.

Can anybody please give me a hint whether this is possible at all and if so how this can be implemented.

Thank you and best regards,