: Only the host of a multiplayer game needs to own the DLC; all other players will have access to that content for the duration of the session.

: Paradox offers a monthly subscription model (typically around $5/month) which provides legitimate access to all DLC content without the security risks of third-party unlockers. KyLaEga/EU4-DLC-Unlocker-macOS - GitHub

Several EU4 DLC unlockers are available, each with their own strengths and weaknesses. Some popular options include: