I did it with a similar team composition. However I used 5* Celica, 5* Hector, 5* Setsuna, and 5* F.Corrin.

Hector, Tharja, Sharena, and Jeorge, in a horizontal line with Hector being on the left aggro space and Sharena on the right aggro, Tharja in the trees and Jeorge on the far right, next to Sharena.

Hector will take care of one of the green axes, and also damage Camus severely so you can kill him with another shot on your next turn.

Sharena's gonna have to tank two hits, one from the other green axe and one from the healer so in this case, you will want to defensively buff her as much as possible (and Spur Def helps too).

Tharja being in the trees can snipe the green axe that attacked into your Sharena on your following turn. You will want to reposition her to safety afterwards, or you can use her to attack the other red mage later.

Jeorge will take care of the healer.

If it works out, you should only be left with the red mage as the last remaining enemy unit, and he should technically be outside of attack range for Hector.

See if this works.