Is it possible to change the name of an existing custom entity which was created earlier?
On the Admin Console, this field was disabled. In other words, it is not editable.
According to the KnowledgeCenter, it only mentioned that the type cannot be renamed, but didn't mention about the name itself cannot be renamed. You may refer to the following link:
No, there is no facility to rename the custom entity. The workaround was to delete the entity and recreate it again.