Can I use different format settings for the same variable? For example, I would like the variable "Telephone Number" to have 3 different formats for 3 different countries.

No, one variable can have only one format option from the list. We can suggest creating several different variables and setting the required parameters for each of them. Here's an example: Telephone1 will be in the +1 format, Telephone2 in +49 format, etc.