All Young Avengerss have already appeared in the MCU except for Hulkling. I have 3 projects that he possibly will make his first appearence.
Secret Invasions: Very high probability, because the serie's plot involves Skrulls and possibly Krees, and Hulkling is a Kree/Skrull Hybrid.
The Marvels: Moderate-high probability, because as I said before, he is a Kree/Skrull Hybrid and Captain Marvel has a very strong connection with Krees.
She-Hulk: Attorney at Law: No-low probability, I hearded some people saying that he could appear in She-Hulk: Attorney at Law, but I honestly think that the probabilities are very low.