Yes, players move from CF to LF all the time, but Duran is just learning the OF, and if he is to be called up very soon, they'd be playing him where they expect him to play already.
Why LF? He'll be replacing Kike not Verdugo.
If we dump Santana to call him up, Kike would play 1B orplatoon with Dalbec there and Marwin at 2B, until Arroyo returns.
Of, we just platoon Marwin with Dalbec and play Kike at 2B. (I don't see Marwin as a better hitter than Dalbec, even vs RHPs.)