-Two main antagonists from horror media who were actually once normal serial killers (William Afton and Charles Lee Ray) who went by other names (the Lakeshore Strangler and, although unofficially, Purple Guy) but were later forced to possess child-friendly mechanical objects after being chased down by people who opposed them and vice versa (William, although unintenionally, hid and later died inside of the Spring Bonnie suit after running away from the spirits of his victims, possesing it, and Charles used voodoo magic to possess a Good Guy doll before he died while being chased by authorities).

-Their main target are children, which they only go after for selfish reasons (William killing various children just for that sweet, sweet Remnant and Charles, now Chucky, going after whatever child he can get his hands on as a vessel for his soul to possess). Both can be rather manipulative with these children as well and often try to seem friendly with them just to play out their plans.

-For whatever reason, both seemingly just can't die and always come back through the dumbest ways possible.

-Due to their actions, they gave the respective companies of their series (Fazbear Entertainment and Play Pals) a bad name.

-Both have had at least one different body as the story goes on (Springtrap becoming Scraptrap and later Burntrap and Chucky being reborn in a new body due to his blood falling into the toy's molten plastic, plus his pseudoclones in Cult of Chucky might be an example, along with other stuff).

-Both have had their stories and whatnot turned into some weird meta fictionalized media within their canon (Fazbear Entertainment creating the Fazbear Virtual Experienced and the Chucky Goes Psycho movie in Seed of Chucky) which they indirectly become somewhat of a part of (William presumably becoming Glitchtrap, or at least some replica of him, a living virus that inhabitd the game and Chucky later possessing the animatronics built for the movie thanks to his, uh, son?)

-Speaking of, both are probably not the best dads (Much more apparent with William than Charles, since he actually seemed to care for his son, although that didn't stop him from strangling him with his severed arm once he was a human boy).

-Their sons (specifically Michael Afton and Glen) are comparatively much nicer, purple-clad characters who were originally doing their own thing, but later went on a quest to find them. They eventually did, which ended up in both William and Charles """dying""", but... Y'know that wasn't the case.

-Both were burned "alive" TWICE (maybe more times) and somehow survived or just came back (Springtrap was in the Fazbear's Frights building when it was set on fire but he somehow survived, and later was burned in Pizzeria Simulator but still came back. Chucky was burned in his first movie but was still walking around and he was inside of Lexy's house when it was on fire in the new series but he still lived).

-Both at one point used their powers to take over a girl to manipulate them into doing their bidding (Although this is mostly speculation, William/Glitchtrap took over Vanessa's mind, turning her into Vanny while Chucky possesed Nica in Cult of Chucky). Said girls were protagonists in earlier installments (FNAF: Help Wanted and Curse of Chucky) where they first met our fighters.

-Bonus Connection, maybe: Chucky and Glitchtrap in particular both share the same kind of goal (Serial killers trapped in a new form and they desire to escape this vessel and use the protagonists body as a means to get out).

-Oh and their series got weird later on lol

Connections so far