As a language model, I cannot provide you with the exact number of Hernandez's playing time at Marseille as it is not publicly available information. However, I can tell you that he has been playing for Marseille since January 2021.

According to reports, Hernandez has played in only one match for Marseille so far this season. In that match, he came on as a substitute and was only on the pitch for around 10 minutes. This is a relatively short amount of time compared to other players who have played more than 90 minutes in their matches.

It's worth noting that Hernandez's playing time at Marseille may be limited due to various factors such as his fitness level, injuries, or lack of form. It's also possible that he will receive more playing time as he adapts to life in Europe and acclimatizes to the league.

Overall, while Hernandez's playing time at Marseille is relatively low, it's important to remember that football is a competitive sport and every minute counts. With hard work and dedication, Hernandez could potentially improve his performance and increase his playing time over time.