Hi!
The grouping is definitely an issue, I don’t think it is possible with that feature enabled.
Variation Name
Thank you for that code. From what I can see, he is trying to add a specific product attribute to the variation title. He was using a different code, but that won’t work with the current WooCommerce version.
What I don’t understand is, what the variation title should be? Do you want to display product variation attributes within the product title?