I’ve been doing some testing with the Essential Graphics panel and how it interacts with Templater, and while I think you can use Templater to set the graph variables, you’ll most likely have to do it in the timeline directly.
If you right-click on the value that you want to change in the Essential Graphics panel and choose “Reveal in Timeline” that should display the value in the project that is controlling the graph size. Once you know the location of that value, you should be able to get more direct access to changing it.
First, you’d want to add a text object to the project and apply Templater to it. This will be the value you’ll change in the graph setting, so 25, 70, etc. Next, you’ll want to customize the Expression in the field we found earlier by clicking on the value while holding the Alt or Options key.
Once you’ve got access to that line, you’ll want to add a reference to the variable you brought in previously. In a test, I used something like:
parseInt(thisComp.layer("<variable layer name>").text.sourceText)
This replaces the value in that layer with the number that was brought in earlier. It’s a bit tricky, but those are the basics of using Templater to designate a variable in a project. It’s hard to give specific instructions without direct access to the file, but hopefully, that should get you started. If you have any other questions, please just let us know.
One final note. Once an expression is controlling the layer, you’ll no longer be able to change the value using the Essential Graphics panel.