transborder
adjective
trans·bor·der tran(t)s-ˈbȯr-dər 
tranz-
: crossing or extending across a border
Example Sentences
Recent Examples on the Web Alarms across the world In 1970 governments around the world were contending with transborder pollution challenges. 
Maria Ivanova, The Conversation, 16 Apr. 2020
Maria Ivanova, The Conversation, 16 Apr. 2020 Word History
First Known Use
1897, in the meaning defined above