Using CC-BY ZEro Models in marketplace assets

Hello There, I’m making Blueprints that I will see in Marketplace, I might need some models in it, Can I use CC-BY Zero 3D models instead of making one ?

Content being sold in the UE4 marketplace must be owned by you. In the case of blueprint and code based projects you can use Epic content for the purpose of demonstration so long as it isn’t the primary focus.

What if I asked the creator of the model and he agreed ?

That would be between you and the creator then. You’re going to want to provide Epic with proof of that in order to avoid any potential issues.