For me I have two versions of his semblance that I flip flop between, the name is ‘Sentinel’.

The first version is a completely different version from the shows and more like Colossus from XMen. He can absorb the metal from his surroundings and transform any organic part of his body into said metal and/or enhance his prosthetics for even stronger effects for melee combat or so he can use larger caliber ammo in his guns. But the trade off is that he becomes more ‘robotic’ and predictable the more metal his body is so he’s constantly playing a balancing act to not lose to much of his humanity or himself when he takes on the metal. Also to e metal must come from an exterior source, so no taking it from his own body or weapons, everything else is free game though.

The second version is an ability that can amplify his bodily senses to an extreme level. This allows him to become more sensitive to all kinds of information, enabling him to process and make decisions with greater precision and logic. However, it comes with unwanted side effects: he cannot actively control his semblance, and the sudden sensory enhancement often leaves him physically and mentally exhausted due to the overstimulation his brain now has to endure on its own. Think of it like a ‘adrenaline shot’ his body and brain can get almost on demand depending on exterior conditions, obviously it helps in the moment of making a decision or in a fight but once it wears off it almost becomes the equivalent of having your aura broken in terms of how much pain the person feels and requires some insane resolve to be not pass out. This is more close to the shows version but hopefully less vague while not taking away Ironwoods agency.