You might not want to do that. Using the official Vesteria logo, name, etc. would be copyright infringement, since the name “Vesteria” is copyrighted. You could get in some trouble for doing so, especially if it’s not explicitly approved by the copyright owner (who I’d assume is berezaa).
A similar thing happened a while back where someone wanted to make an unofficial Vesteria shirt on Roblox with the word “Vesteria” and the Vesteria logo, and were even planning on putting all money earned from the shirt right back into the game through either buying it on other accounts or buying Ethyr, but David explained that they weren’t allowed to make the shirt either way and told them to stop.
If you were to be officially allowed to do so, then it would be fine, but otherwise I’d hold off on it just in case.