Maul is introduced towards the end of S2. There’s definitely stuff before that you need, but it’s pretty episodic so it’s easy to pick and choose. I’d recommend trying to find a list of essential episodes somewhere. Some of the inquisitor stuff shouldn’t be skipped, but you might not need all of it.
It should be noted that I haven’t rewatched the show since it originally aired, so I could be off base here. This is just my years-later recollection of it.