Seems to be a requirement to own the base game Europa Universalis IV on GOG.
Most people on here will likely have claimed the game for free on Epic:
launcher.store.epicgames.com/en-…ack
Most people on here will likely have claimed the game for free on Epic:
launcher.store.epicgames.com/en-…ack
STEAM - Before you can add this product to your Steam account, you must own the base product.
EPIC -(If you managed to get the game free !! ) store.epicgames.com/en-…ack
Also Fee from Epic -
Europa Universalis IV: Evangelical Majors Unit Pack - store.epicgames.com/en-…ack
Europa Universalis IV: Songs of Yuletide - store.epicgames.com/en-…ide