Many characters shone throughout his character arc being one of the best of the season and his death utterly gut-wrenching. One of the worst parts of him dying in the same season of his debut when all of the major characters seemed to be divided among separate storylines was that he never got to interact with some other fan favorites.
With some characters in Russia and some traveling from California until the very end of the finale, Eddie was left unable to form what could have been some interesting and fun dynamics with many of the major players in Stranger Things.
Officers Powell & Callahan
It was not simply characters being in different parts of the world that kept Eddie from interacting with characters; rather, in this instance, it was good hiding and bad police work.
Despite looking for Eddie for the whole season, Chief Powell and Officer Callahan never actually interact with the heroic character. Them looking for Eddie did lead to some good moments and an interesting commentary on the very real Satanic panic of the eighties, but Eddie evaded them for all nine episodes.
Murry Bauman
Murray Bauman was fantastic comedic relief throughout season 4, bringing some levity to the Russian portion of the season. But being on the hunt for Hopper with Joyce did mean fans were deprived of some weird potential interactions with Eddie.
There is a very real possibility that even if they were in the same area, Eddie and Murray would not actually have many solo conversations. If they did, though, they would likely be hilarious, with both characters being not only loud but eccentric as well. It is hard to imagine what they would have bonded over past that, though.
Joyce Byers
There is definitely a rebellious side of Joyce Byers that would have appreciated and perhaps even related to Eddie. She would also be sympathetic to his struggles with Upside Down, given all the trauma she has endured because of it.
What could well have united these characters is Joyce's built-in protectiveness, which would have led to her comforting Eddie even if they do not have a lasting connection. Alas, these two season 4 MVPs never got the chance to meet, with Eddie instead forming a newfound friendship with the other main mother of Stranger Things, Steve.
Jim Hopper
If Hopper returned to Hawkins P.D. in Stranger Things 5 and Eddie had lived, it would have led to a fascinating situation where Hopper, most likely, would have done his best to look out for and protect him in the fight to prove his innocence.
But while Hawkins police were trying to put Eddie in prison, Hopper was in a Russian jail and did not get to share any screentime with any of the main characters outside Joyce and Murray until the final scenes. It does seem plausible that these two characters have met before, though, with Hopper perhaps having to arrest Eddie on a couple of occasions for misdemeanors.
Argyle
Eddie and Argyle could well have been one of the most iconic duos on Stranger Things had the writers decided to have them meet. They completely juxtapose one another aesthetically, but their whole energy together would be hilarious.
There is an obvious connection between these two in that they are recreational drug s and, on top of that, are both hilarious and eccentric. That would only aid their potential friendship had they appeared together in season 5. Fans will undoubtedly feel as though they were robbed of a legendary odd couple.
Vecna
Technically since the Demobats appear to be a part of this Vecna hive-mind, the two did indirectly interact. However, the Jamie Campbell-Bower-portrayed-villain and Quinn's Munson do not share the screen in the show.
Eddie may have loved being the Dungeon Master in D&D games where Vecna is the villain, but it is likely he would have been endlessly freaked out, frustrated, and scared had he had to face off with the powerful being before the finale. Had he ed Nancy, Robin, and Steve, it is easy to imagine his inner bravery and heroics shining through.
Jonathan Byers
Jonathan and Eddie would have had a lot of potential to form an exciting connection going into the show's final season, especially in creating a pretty wild trio with Argyle. But, being a part of the Cali-crew meant Jonathan never made it to Hawkins in time to share the screen with Eddie.
They have a bit in common that would have meant some great interactions, though. They both consider themselves freaks, they both have a deep care for their friends/family, neither fit in with the cool and popular crowds, happy to instead be on their own paths, and they both have great music taste, which perhaps deviates from others in the show and of the time.
Wayne Munson
Wayne Munson obviously interacted with and had a relationship with Eddie; he is literally Eddie's uncle and seemingly his guardian too. However, tragically, the two are never shown interacting on-screen.
In many ways, this was a genius move, as it makes each of their stories in this season that much sadder. Who knows how this season would have been impacted had Wayne been there when Chrissy died. The fact that they did not see each other through this ordeal not only makes Eddie's death sadder, given that he did not get to say goodbye to a man who truly loved him, but it also makes Dustin's conversation with Wayne in the finale that bit more crushing. Both Wayne and Eddie deserved better, happier endings and lives this season.
Eleven
Busy on her quest to regain her powers and then help out Max and her friends defeat Vecna from a distance, Eleven never gets to meet Eddie, and that's pretty heartbreaking.
There is so much potential here for another great big sibling/little sibling relationship, where Eddie would unquestionably be fascinated and appreciative of El's differences and badassery, as well as her relationship with Mike. All the while, El likely would be a bit taken back by Eddie at first before growing to love him.
Will Byers
The fact that Eddie Munson and Will Byers never got to interact and will never get to interact is one of the biggest crimes committed by Stranger Things 4. They would have been such fantastic friends.
The interplay between them would have stretched beyond a shared ion for D&D. These are two characters who don't fit into social norms and are well aware of that fact. But while Eddie gladly accepts it, Will struggles with it. Eddie could have helped Will have more confidence in himself and his differences, just like Jonathan does. Of course, D&D would still play a part in this dynamic, as Will would have reveled in Eddie's epic campaigns too.