French Address Field

is there a French address block available ?

Inside of JotForm you can change language of your account to French. In that case Address Block available inside of the Form Builder will be translated on French. 

You can set your form to be multilingual. To see how to do it please read this guide:

http://www.jotform.com/help/298-How-to-make-your-forms-multilingual 

Hope this will help. Let us know if you need further assistance. 

Is it possible to mask "état/province" and "pays" from this block ?

Are you referring to the "Input Mask"? If yes, then the answer is no. You cannot assign input mask on the address fields because it is created under Quick Tools. However, if you create a separate text box, it is possible to use the input mask.

If what you mean is changing the sub label, then you just need to double click the text and change it.

Hope this helps. Thank you.