Technically he'd probably OD and die. Estrogen is measured in pg/ml which is 1/1000 of ng/ml, which is what T is measured in.
So... typically a male has, let's say, 500 ng/ml of T in the blood in the blood. 500 ng/ml would equate to 500,000 pg/ml of estrogen. The normal amount for a cis male is under 50 pg/ml, and the normal amount for a female is (depending on the time of month) no higher than 450 pg/ml .... So I'm sure liver failure would happen happen and death would occur.
Estrogen is MUCH more potent than T.