Usually, the trial CMS projects are created in the latest Umbraco CMS version, but if you want to create it on an older CMS version, such as v13 project as a free trial, I'd be happy to help clarify the options available to you 😊
You should be able to use the following steps to create an older CMS trial project:
Select Create Project from the Cloud Portal
Select Umbraco Cloud as the Type
Select Starter as the Plan
Select Show older versions and then select the older version (example: Umbraco 13)
Under Project Ownership, select the 14-day trial project option
Continue to create the project, and you should be good to go 😁
