Lmfao you can try to jump right in to Duck Life 4: Quack Attack if you want, but the upgrade system that was introduced in Duck Life 2: The Requackening will basically be a mystery to you. Especially since they revamped it in Duck Life 3: King Quack arises. And the story is non-sequential as well, so if you want to play it chronologically you go, 2,1,4,3. But it’s really better to play in release order IMO, the characters of Sir Quakston and Quckarella have a better arc that way. I’m really frustrated with how they made that stupid love triangle shit cannon.
Anyway yeah you can jump right into 4 if you want.