Steve has a moment of visceral unease about the sword, accompanied by a desire to put down some more lines around this, make some strong reminders, have that entire discussion.

He covers both of those by taking his hat and sunglasses off and leaving them near the door, and takes a couple of deep breaths and goes over what his own plan is here, and with Clint. No outward demeanor change, no weapons, no external defense. Space and his body.

"I'm good."

Which is about the warning he gives before he turns around, faces Clint, gives him a slight nod, and then moves. Not just moves, but goes in with speed and intensity from the start.

Learns and adapts. Takes hits himself along the way, because Clint's really good (though specifics are down to Clint). Steve keeps the hardest of his own hits to Clint's upper back, ribs, and even backs of his thighs. Pulls his punches enough not to do serious damage, but not too far. Cracked ribs, bloody nose, bruises deep enough that in the meatier areas of Clint's body they're likely to turn more black than blue. The occasional finger print shaped bruises and scratches.

And he's not likely to let up until Clint either asks or is visibly starting to flag.