Warning! Spoilers for The Boys comic series and television series below.
The most horrifying kill by Homelander in The Boys' comic book is likely too brutal and gruesome to appear on the television series. In issue #40, Homelander's past as a hero is revealed, as he is seen ripping apart and feasting on actual people - including a baby. However, it was later revealed that the patriotic and psychotic villain wasn't truly responsible (sort of).
In both The Boys television and comic book series, Homelander is one of the scariest, most dangerous Supes alive. A parody of Superman, Homelander couldn't be more different morally from the Man of Steel. His ego and short-temper have led to the deaths of hundreds, including the time he refused to save children on a plane full of people that was hijacked because it would potentially ruin his image. Homelander is a bad dude, who's terrible upbringing doesn't forgive the atrocities he regularly commits as the supposed bastion of hope. Believe it or not, his actions are worse in the comics.
The Boys' comics by Garth Ennis, Darick Robertson, Tony Avina, and Simon Bowland made a horrifying reveal about Homelander in the series fortieth issue. In the scene, Vought-American executive James Sitwell is breaking down an incident to senior officer Jessica Bradley that occurred with Homelander more than 20 years ago. Described as a unique, one-time occurrence, it's revealed Homelander was once pushed too far, which led to him eating and ripping apart people. Most disturbingly, he ate a newborn baby (the images too gruesome to include in this post).
While The Boys series on Amazon hasn't been shy about showing some incredibly messed-up and violent scenes from the comics, including Homelander eating a baby in live-action would be a step too far. It's too disgusting and isn't worth adapting as it's just shock value gone too far. Plus, in the comics, it's revealed that Black Noir is actually a Homelander clone and committed his worst atrocities - and the show seems to be going on a different path with the character, so it's unlikely cannibal Homelander (actually Black Noir) ever happened in the show's universe.
Ultimately, the scene from The Boys' comic is one of the vilest things ever printed in a comic book. There's no clear advantage or need for the show to adapt it, so it's best it remains as a comic book moment only. The Boys television series isn't afraid to get gross or screwed up when it comes to bringing the comic to life, but Homelander eating babies shouldn't - and will likely never - see the light of day on the show.