I'm curious why it's required to have that many attributes on an entity, I would definitely discuss that before implementing.
An alternative approach could be to implement a key-value list of properties, like this:
If you do want to continue as proposed, you can make use of the Mendix SDK to interact with your Mendix model via scripting. It's using NodeJS and you can alter a project in this way. More info: Introduction Mendix SDK
Good luck!