Some specific online game titles may be rated "AO" (stands for Grownup Only), pinpointing games that have articles appropriate for only Grown ups around the age of eighteen. Moreover, online games need to also have an ESRB see that warns that any "online interactions are not rated via the ESRB". https://zzxab.com/the-evolution-of-gaming-from-pong-to-virtual-reality/