Pepper Potts could be a big help. She knows Tony so well, and she could try to jog his memory by showing him things from their past together, like pictures or mementos. Rhodey could also be there for him. He could tell Tony stories about their military days and how they became friends, which might trigger some memories.
One common character paired with him is Bruce Banner. They could be gaming buddies, with Bruce using his scientific knowledge to help Tony improve his games or vice versa. Another is Pepper Potts. She might be shown as someone who tries to get Tony to take a break from his intense gaming sessions.
In a fanfiction, Tony Stark's adaptation to Winterfell life would be a journey. At first, he'd be completely out of place. His shiny Iron Man suit would stand out like a sore thumb among the furs and leathers of Winterfell. But he's smart. He'd start by making small changes. He'd use his engineering skills to improve the living conditions in a way that's acceptable to the people there. For instance, he could design a better heating system for the castle that doesn't rely on modern technology but still uses some of his scientific principles. He'd also have to adapt his language. He's used to using technical jargon, but in Winterfell, he'd need to communicate in a more straightforward and simple way. He'd gradually become part of the community, participating in hunts, helping with the harvest (if there is one), and eventually becoming a respected figure in Winterfell, all while still maintaining his unique identity as Tony Stark.
In a fanfiction with this theme, it could explore how their 'hard knock life' experiences shape their characters differently. Tony might use his wits to survive the cut - throat business world earlier, while Steve could be more focused on community and helping those around him. Their paths cross when they realize they are both fighting for a better world, but from different angles.
One common character paired with him could be Pepper Potts. Their relationship could be explored in a new light with Tony having psionic powers. Maybe Pepper has to deal with a more powerful and sometimes unpredictable Tony.
It could be Rhodey. As Tony's long - time friend and fellow Avenger, Rhodey would be eager to see him and would likely be among the first to be informed of his return.
His parents, Howard and Maria Stark, are very common. They play important roles in shaping Tony's childhood. Jarvis, the family butler, also often appears. He could be the one to encourage Tony's scientific pursuits or keep him out of too much trouble.