Is there a grain-free dry food that is better for hairballs?

When Matilda eats dry food, she eats Natural Balance Green Pea & Duck. I started feeding her grain-free food to see if it helps her skin. So far it's been about 2 weeks and it does seem to be helping.

She used to eat Nutro Natural Indoor Dry, and when she did I never had a problem with hairballs. Now she gets them very frequently (even with regular brushing). She has very long hair.

I have some of the natural hairball gel stuff that I am mixing with her wet food but she doesn't seem to like it.

Is there a grain-free dry that could be better for the hairball issue?

Orijen and Taste of the wild worked for Zoey

I don't know of any grain-free dry food that is supposed to help with hairballs (which certainly doesn't mean that they don't exist). It may be a case of trial and error specifically with Matilda, which unfortunately means lots of transition periods as you slowly introduce the new food, and possibly lots of money wasted on the foods that don't work for her.

Maybe you could go to the websites of some brands that produce grain-free dry, and briefly explain your situation to them and ask them to send samples. From what I've read, it's commonplace for many companies to send out samples, and given your situation, a company could have a customer for the life of the cat if their product does the job. Lots of potential upside for them here.