Where that connects to Sentry is the fact that Pullman’s Marvel character has been rumored to serve as the movie’s main antagonist. Sentry is a hero in Marvel Comics, and the character should start like that in the film. However, rumors claim that Bob Reynolds will turn to the dark side and go up against the team.
Given Sentry’s immense power — he is one of Marvel’s Superman-like characters — and the MCU’s Thunderbolts mostly being made up of super-soldiers, the team would not be much of a match for Sentry.
While Sentry is a hero, Bob Reynolds holds great darkness within him. In the comics, when Bob got his powers and became Sentry, a dark entity known as the Void bonded with him. Eventually, that twisted power took over and led to a path of death and destruction.
It would be interesting to see Sentry first become part of the Thunderbolts, with the team rumored to rescue him from the vault that appeared in Florence Pugh’s Thunderbolts* set video before fighting Pullman’s character as the Void in Marvel’s Thunderbolts*.