Originally Posted by
greatmetropolitan
MCU Vibranium isn't unbreakable - just ask Cap's shield. Without knowing exactly what Thanos' blade was made of then we can't call it Vibranium, so it's just a brute strength thing. Thanos' strength is hard to pin down as it's all in relation to other characters and not something he does alone, like a lifting feat or punching feat. But he's strong enough to gradually overpower Thor and Hulk, whose strength levels are kinda all over the place.
WW can hit hard enough to make Superman wince, and he's a guy who took a nuke while explicitly weakened and didn't die and whose fight with Zod, which included re-entry, didn't appear to leave a scratch on him.
Plus WW's sword is good enough to dismember Doomsday, who took a nuke and hits from Superman and kept on trucking. If she can hit Vision, she can hurt him. It's just down to if she can cross the distance before he phases.