Looks like the jury is still out on whether there is a relationship between violent games and antisocial behavior:
"Research on gaming effects has focused on adolescence, a developmental period in which peer relationships become increasingly salient. However, the impact of peers on the effects of violent gaming on adolescents has been understudied. This study examined whether adolescents’ exposure to violent video games predicted their own and their friend's aggression one year later. Among 705 gaming adolescents, 141 dyads were identified based on reciprocated best friend nominations (73.8% male, Mage = 13.98). Actor‐Partner Interdependence Models indicated that adolescent males’ (but not females’) exposure to violent games positively predicted the aggression of their best friend 1 year later. This effect appeared regardless of whether the friends played video games together or not. The study illustrates the importance of peers in the association between violent gaming and aggression."
Verheijen, G. P., Burk, W. J., Stoltz, S. E., van den Berg, Y. H., & Cillessen, A. H. (2018). Friendly fire: Longitudinal effects of exposure to violent video games on aggressive behavior in adolescent friendship dyads.
Aggressive behavior,
44(3), 257-267.
https://doi.org/10.1002/ab.21748
"The relationship between violent digital games and youth behavior remains contested in the scholarly literature. To date considerable scholarship has focused on university students, with fewer studies of adolescents or children. The current study examines correlational relationships between violent game exposure and bullying behaviors, antisocial attitudes, civic attitudes, and civic behaviors in a sample of 304 children from the United Kingdom (Mean age = 12.81). The paper also considered motivational influences on use of violent digital games. Results indicated that violent game exposure did not correlate meaningfully with either antisocial or civic behaviors or attitudes. These results are discussed in a motivational and developmental context. (PsycINFO Database Record (c) 2018 APA, all rights reserved)"
Ferguson, C. J., & Colwell, J. (2018). A meaner, more callous digital world for youth? The relationship between violent digital games, motivation, bullying, and civic behavior among children.
Psychology of Popular Media Culture, 7(3), 202-215.
http://dx.doi.org/10.1037/ppm0000128