It may be that such a license can’t exist. The way these viral copyleft licenses work is that they offer things to people who accept them that copyright otherwise doesn’t permit. The usual example: you can distribute copies of this work (a thing that copyright prohibits you from doing by default) but in exchange you must release any derivative works you make under the same licence.

The problem is that you actually can reject that licence. You can download the software (that’s allowed because the person distributing the software agreed to the copyleft license) and then decide you’re not going to accept the license that came with it. At that point you’re restricted by ordinary copyright and can only do the things you’d normally do with it.

There have already been court cases in the US that have ruled that training an AI is fair use, and the resulting model is not a derivative work covered by the copyright of the original. So you can just go ahead and train the AI at that point.