We tried Catan Junior today. It’s fairly well done.
As you’d expect, they rounded the sharp edges off of Catan. You don’t lose resources on a 7, and the robber doesn’t steal from you directly. Part of this is making trading with “ports” easier, so players are stuck less often. The development cards are far more powerful.
All of these measures in the service of friendliness actually make the game less predictable. A lot of Settlers games can be called after initial placement. And for kids, figuring out what you can pull off with various resources is exciting.
The end conditions seem to have not thought about the two-player board, though. You have to build 7 lairs to win. We filled the board and had 5 and 5 (sometimes 6 with the pirate island). It seems hard to hit 6 + pirate island without being blocked.
Regardless, it is engaging for an hour.