More fields "Product Variations"

Hi there

I like to sell courses with MarketPress. We sell course on different dates and different places. So I need to customize the product variations. I’ve attached a screenshot how it should work.

At the moment I have “date” as a production variation and I like to have the fields “place” and “course type (walk in, online, …:wink:” as a dropdown in the “more box” of each product variations. How can I do that?

Thanks and best,