Most resolution mechanics in tabletop RPGs consist of player ingenuity, character ability, and some kind of dice roll or card draw. Generally, these resolution mechanics are used for their probability distributions, convenience of use, availability, to be a meta-component of the setting (e.g. poker chips and poker card mechanics for Deadlands), or just because they're fun.
Let's lean into those latter two. You know what else is fun? Videogames! So the obvious thing to do would be to use a turn-based RPG, tactical RPG, or "Infinity Engine"-style game, especially if it has a custom game editor, and literally simulate the tabletop. That's fun in its own right, but at that point why even have the tabletop? Also, that's too obvious. No, this isn't about a digital simulation for resolution, this is about using videogames as an abstraction, like dice or cards.
It would be best to choose a game that is fast, relatively easy, and that your players have roughly even skill or familiarity with, and is customizable. I'm going to use Super Smash Bros. as my example here, but it doesn't have to be a combat game, it could even be a competitive puzzle game like Puyo Puyo.
So with smash, by default, you would pick a character which is most like your character (you don't have to do this, but it might be better this way meta-narratively). Depending on your level relative to your opponent's, you could give yourself or the opponent handicaps (e.g. extra lives, higher starting damage, w/e else can be customized). To simulate spells or special abilities, you could only include certain items on the stage, and artificially impose a rule that only a character that should have that ability can use that item (for this reason, you wouldn't want to play against a bot). I haven't played smash ultimate yet actually, but if it has customizable fighter stuff, which I believe it does, you may be able to simulate character stats even more directly.
You probably want to have a very short time limit, or a low-stock game (even one stock), and want to play on a smaller stage (ideally one most like the environment of the conflict), or with a high starting damage, to keep things snappy. If there is a major imbalance in player skill, the player can allow someone else to play for them, or the GM could have one of the players play in their place, but if this is going to regularly be the case then you probably want to play a different game.
You could make each RPG conflict turn a videogame match, where the winner of the match then rolls their damage dice, or simulate an entire one-on-one encounter this way, where the loser of the match dies / is defeated in the RPG conflict.
You could even replace tabletop RPG combat altogether with this, having a team fight with all players against all opponents (although this would only work if you have a few extra people around to help the GM, or are ok with pairing the GM with bots who might not follow the item rules). Depending on the game (both tabletop RPG and videogame), you could use this for not just combat conflicts but potentially other kinds of conflicts as well.
This is maybe a bit of a novelty idea, but I think it could be fun. Here are some reasons why you should try this:
- Videogames have a degree of inherent fun.
- It's potentially a lower barrier to entry for new players.
- If the videogame is a good meta-narrative fit with the campaign setting of the RPG then it could add to immersion.
- It adds a unique kind of player skill that you don't normally see in tabletop RPGs.
- It's a different kind of engagement with the game, if your players sometimes struggle with staying focused.
- If you find the right game, it can be faster than usual tabletop conflicts.
- It requires less prep / can be done on the fly.
- You can get more people involved in the game, even if they aren't playing the RPG directly.
- You could build a whole campaign setting around this, with different games as in-universe challenges and different characters in those games as avatars or champions of the players / PCs.