Difference between Hybrid Hosting model and Split with Cloud messagaing Deployment model?

The main difference between the Hybrid Hosting model and the Managed Services / Hosted  model in Adobe Campaign is where the customer data is located.

Hybrid Hosting model

In the Hybrid Hosting model, the Adobe Campaign solution software resides on-premise at the customer site, and execution management is delivered as a cloud service by Adobe. This means that the customer is responsible for maintaining the on-premise infrastructure, while Adobe takes care of the cloud-based infrastructure and the email execution engine.

Managed Services / Hosted Model

 I am not sure if there is any deployment model with this name Split with Cloud messagaing Deployment model in Adobe campaign. 

 I believe your mean Managed Services / Hosted Mode. 

In the Managed Services / Hosted Mode model, Adobe takes care of managing all aspects of the Adobe Campaign solution, including the on-premise infrastructure, the cloud-based infrastructure, and the email execution engine. The customer is still responsible for providing the data and for configuring the solution to meet their specific needs, but they do not have to worry about managing the underlying infrastructure or software.

Which deployment model is right for you depends on your specific needs and requirements. If you are unsure which model to choose, you should contact Adobe for assistance.

 Please check the following documentation for more information. 

https://experienceleague.adobe.com/docs/campaign-classic/using/installing-campaign-classic/architecture-and-hosting-models/hosting-models-lp/hosting-models.html?lang=en

Thanks, 

Parvesh