Am I allowed to remove / edit the copyright notice in the footer?

It is not compulsory to provide any credits or links back to eVision Themes(https://evisionthemes.com/ ), although we would highly appreciate if your do so. To modify the copyright notice you will need to edit the copyright.php file.
Or you can upgrade to pro version to remove copyright notice in the footer.
https://evisionthemes.com/product/tag/premium/