Does Helldivers 2 have cross-play, cross-progression and/or cross-buy?

Helldivers 2 features cross-play between PC and PlayStation 5, so you can play with players across other platofrms.

However, neither cross-buy nor cross-save/cross-progression are currently available, so you will not be able to continue with the same account across different platforms, and any progression, DLC or limited-time content will not be available to you if you begin to play on another platform. Player support will not be able to merge accounts to transfer items for you.