I want to say John Wick, mostly because his endurance is completely insane. The amount of punishment he goes through is nuts, and he doesn't ever stop. He also frequently fights opponents as dangerous as himself. The Equalizer tends to be a wrecking ball against small fry, but John Wick goes through gauntlets of legendary assassins one after the other like he is in a Mortal Kombat ladder.
John Wick in a direct fight. Just on a whole other level with how he mows down mooks. Especially by the third movie where he’s basically a one man army
Equalizer is better at CQC than John but he won’t get to that point. John’s suit is also bulletproof which is a huge gamechanger
John also packs bigger firepower than Denzel with prep if we’re using his JW2 loadout. Den tends to go on the more light side outside of equalizer 2 where he was using automatic rifles in his duel with Pedro’s sniper character
In an ambush scenario Denzel might have a better shot since with prep time and gear he can get really creative with setting up killrooms.