Medina will most likely be the second healer you get in your Triangle Strategy party, but she works differently than Geela. Her medical abilities are tied to items as she has to ability to use two items in one turn, throw items further, and use healing items to more significant effect.
The thing about Medina is that using her costs money as you’ll have to buy healing items constantly. She should never replace Geela as Medina doesn’t have a lot of use besides using items, especially in the early game. Her double items skill also costs three TP, meaning you can use it sparingly unless Julio is her constant companion.
Medina doesn’t have much use as a physical unit, but you can use magical attacking items for extra damage against enemies. She does have great speed and can improve her movement by upgrading her weapon, but all of her other stats are rather average. Her stats and abilities put her in a unique position on the battlefield. If you keep her on the back lines, she won’t be in range to heal, but if you put her too close to the enemy, she might die quickly. You also have to get her close enough to the enemy to throw magical items at them, making her vulnerable again.
In the end, Medina may not be the best option for a healer, especially in the early game. If you need a second healer, buy the healing items and deploy her on the battlefield.