^^^^^^ This. ^^^^^^Drop 10 is the lightest you need to go with a player this big.
Drop 9 is the preferred bat for power hitters.
33" is plenty long for top level softball.
Always hedge your bets and give your DD 2 bats to choose from.
Get 'em to a 32" drop -10 as soon as you can. You can always go up from there but you have plate coverage handled and know that any decent bat should provide all the power she can generate.
If the Easton seems too much, get a lighter-swinging 32/22.
I have a team of all 11-year-olds and 10 of 12 swing a 32" bat. Most of them are not as big as your girl though a few are bigger. These girls knock the snot out of the ball, too, and face ASA Class A 12U pitching every weekend.