With the success of 2018's Venom starring Tom Hardy, it is pretty obvious that a sequel would get the green light. The post credit scene revealed none other than the infamous Cletus Kasady, who is the human host for the Carnage symbiote. As many people may not know if they haven't read the comics, is that Carnage is the offspring of the Venom symbiote.
https://www.businessinsider.com.au/venom-carnage-after-credits-scene-explained-2018-10?r=US&IR=T
With Venom being rated PG-13 and being as violent as the character is in the comics had some viewers feeling apprehensive as they did not know if the movie would turn out to be marvellous. So this leaves the question being that Carnage is on a whole different level of violence that his counterpart Venom. At first glance we as an audience would say that the Venom sequel would most definitely need to be rated R. But this is also what we said when we heard Venom was being filmed.
I believe that Venom 2 can be as big a success as the first movie if it is also PG-13, but they may have trouble having that level of violence fit into the child friendly scene of the movie industry. That being said, they did not show the kills during the first venom and this can no doubt be replicated, it is more of a concern of, will the sequel flop as most sequels are notorious for.
Best of luck Sony!
Sup Dork! Enjoy the upvote!!!