Install V4 Studio like any WordPress plugin, then open it once. That first visit adds its variables and classes to Elementor.

Your version is shown in Dashboard › Updates.
Your host's version is shown in Tools › Site Health › Info.
Installed and active. V4 Studio is tested with Elementor 4.3.
Only administrators can open V4 Studio and make changes.
Download V4 Studio as a ZIP file.
In WordPress, go to Plugins › Add New Plugin, select Upload Plugin and choose the ZIP file.
Select Install Now, then Activate Plugin.
Select V4 Studio in the admin menu once. This sets it up.
Activating the plugin adds nothing on its own, and there is no reminder. Open V4 Studio once to add its variables and classes. Nothing is lost if you do it later.
Edit a page with Elementor and select an element. In the Style tab, open the class field: V4 Studio's classes, such as button-primary, are in the list. Its colors, fonts and sizes are there too, as variables.
Yes. Open V4 Studio once from the admin menu. The first visit adds the variables and classes to Elementor.
Administrators. Other users don't see it in the admin menu.
Its own settings are removed, including Brand Data. The variables and classes already in Elementor stay there, because they belong to Elementor.
Next
Quick Start
Make your first changes: your brand, a color and a class.