Cycling is basically always two here, one 'commentator' and one (usually) former cyclist. Since cycling is often quite a long broadcast, that often results in a large part being kind of a conversation between the two, my favourite duo on Eurosport does that perfectly - they were a bit awkward when they started out some years ago, without knowing one another, while nowadays during the broadcasts you can just hear that they have become close friends (often making fun at one another, talking about life and so on)
Formula 1 has two commentators here since this year, after one guy doing it for 30 years or so but the channel that got the rights from this year didn't hire him. That's about it, in terms of two-commentator-sports here
Sometimes some sports have a second commentator if one is available or for some special event or so, but usually not.