You can technically play it all stealth I think. But there are parts where a villain catches you red handed, and sends swarms of their goons your way. I just gunned and blasted my way through those parts. It was possible to try and avoid them and sneak past, although that would probably be very challenging.

The gun play is very fun, too.

Edit: I just remembered there are a few parts where shooting enemies is mandatory, otherwise you die. I’d say if you really wanted, you could make like only 10% of the gameplay combat if you really tried hard?