I rare do time out and it only used for intending to hurt. Hit, bite, etc. Because it rare here it a bit shocking to child to be put in time out.

Like you, I normally, redirect, catch child before, verbally remind if I see something headed so I do time out very different to add to the shock.

I get hold of child and move to time out at quick pace. I plop them in time out and very direct comment like "No hitting" and move away. They stay in time out and then I pick activity that child loves for everyone else do.

When time out done I keep to simple statement. "we not hurt people in Miss Suzie's house" and then child has different toy while others do child's favourite activity.

Shock of be in time out, shock of Miss Suzie not talking lot, upset of being excluded from favourite activity all add to message that not okay to hurt. But must be consistent. Make sure to pay extra attention to victim not perpetrator - lot time, hurting for attention so I make sure focus my attention everywhere but the instigator. Helps be quicker resolve if parent on board too.