Sorry that you have not getting help sooner.
Here is sample automation that might help you figure out on how to do it. PhotoPheaAutomation.zip (2.8 MB)
I Have errors: “Main.xaml: Object Repository usage is enforced. Please add this descriptor to Object Repository or use a different one from existing.”
The Repository is empty as you van see below
I have zip my project there. i am not aware on how to do the export to object repository.
The point is, i am able to use anchor to select the image size easily using drag and drop from activity panel. you could try to create it on your own. Please make sure you have the latest studio 20.10.x to do this.