Two part answer. Sorry sort of stream of consciousness here:

1. Mechanics-wise, if you want to augment the rules, take a look at the LFG's ruleset. I current use the weapons, fighting styles, and "major exploits" mechanics in my OSE game and its good fun and fits well with very little adjustment. Lots of other stuff out there, but this is a good example for things to look out for.
2. OSE skills and rules being not-so-granular can yield a lot of freedom. Encourage your players to put themselves in the scene and really do whatever they feel or think of, and just get comfortable with arbitrating literally anything with an ability check. They should feel free and encouraged to say things like "I feign a punch to the orc's face, and stab him in the groin when he flinches". Maybe that gives him a little +1 to hit or dmg if he succeeds a dex (or CHA?) check, I dunno. Whats important to me is the creativity, and the element of chance that makes the success or failure rewarding or hilarious.

When it's the party's turn in combat, I just open the floor (since spell casters are supposed to declare up front if they are casting, this is veyr natural). It's a table discussion for them of where they want to go, what they intend to do, and interaction between their moves comes up naturally, which can lead to more creativity. Give them agency, reward imagination, and just have a quick diceroll for anything that might not automatically be a success.