Everyone that is writing code or modifying assets (this includes creating blueprints) needs to be able to run the Editor/Engine on their PC. This means programmers, artists and designers. If you want to work in a team, that means source control that everyone can contribute to. If your project includes code, you’ll either need a way to safely distribute binary files to non-programmers or make sure that the other team members can compile after syncing from source control.
It is possible for artists to contribute content to other people without being able to run the engine, but programmers and designers can’t work that way and contribute successfully.