Apple once made a Thunderbolt to FireWire 800 adapter for old-style Thunderbolt 1/2 ports, like the ones on Mid 2012 MacBook Airs. (There were no Late 2012 MacBook Airs.)
If you daisy-chained that with appropriate FireWire cables/adapters (probably FireWire 800 to 4-pin FireWire 400), that would let you make a digital connection, for importing DV video into iMovie. But that adapter has disappeared from the online U.S. Apple Store.
Several Thunderbolt 1 & 2 docks had FireWire ports, as did the Apple Thunderbolt Display (the 2.5K one that Apple sold between 2011 and 2016, not the current 5K Studio Display). But all of those are long gone. (OWC still has one Thunderbolt 2 dock, but it doesn't have a FireWire port.)