So we learned in endgame that the infinity gauntlet is intact technological in nature as iron man was able to recreate it (also the dwarf at nidavelir refers to it as a “device”) enter upgrade, the alien that can control technology. Upgrade could have easily controlled the gauntlet (if not the first then definitely the second one) and simply made it snap thanos. In addition XLR8 could have snatched the gauntlet off of thanos’ hand in the blink of an eye giving him no time to respond. Ripjaws could have bitten thanos’ hand clean off, four arms could have wrestled the gauntlet off of thanos’ hand as four arms is basically a four armed thanos. Goop could have entered the gauntlet and kept thanos from closing his fist. In a similar fashion swap fire or spider monkey could have restrained thanos. Humungusaur would have whooped thanos’ ass. People might say alien X but I don’t believe the two heads would agree on this one because thanos’ goal is so morally blurred however they would have been able to pull it off in endgame as thanos then wanted to destroy the entire universe. And of course because thanos is an alien ben could even scan thanos’ dna to become a titan and be on even ground with him. In conclusion Ben 10 could have defeated thanos in seconds (even with the infinity stones).