The one you linked is also not official, which is Not a good idea to link , because it could be maliciously or weirdly edited. Always use the official versions
skinchanger is not an ESX script, it is a standalone script if you check its code you can see that it does not interact with any code related to the ESX framework. Also, the repository that I have linked should be original.
As the former Owner of ESX, I Can Assure you, Skinchanger is made and owned by ESX, as u can very clearly see in the readme and Licencing in the one you linked. the one you linked is a repost of the ESX 1.1 Version.
I know that skinchanger is made by ESX, however this does not change the fact that skinchanger being a standalone script. It can be a repost because I couldn’t find the original script.