I don't have any recommendations myself but have you tried one of those FURminators undercoat brushes , works wonders on my Maine Coon.
https://www.amazon.co.uk/FURminator-Undercoat-deShedding-Medium-Large/dp/B07NSNHTTK/ref=sr\_1\_8?crid=2ZXTSHNW2591U&keywords=undercoat+brushes+cat&qid=1652698012&sprefix=undercoat+brushes+cat%2Caps%2C156&sr=8-8