Board Thread:Questions and Answers/@comment-32975794-20170828183331/@comment-26500386-20170830141740

Once Izuku masters One For All, yes, he should theorietically be stronger. But since he can't control it yet, he's not even close to rivalling All Mgihts power.

If Izuku and all might clashed at 100%, I'd put my money on Izuku winning, since he has All Mgihts power, plus his own physical Strength.