The meaning of "at range" typically means separated by a (contextually-appropriate) significant distance.
I am not an expert in boxing, but I think two sentences help set the context
Lomachenko boasts graceful feet, honed through his mastery of Ukrainian dance. But he is far from just a mover and his last win [...] showcased an 11th-round attack which ranks as one of the most relentless in recent history.
The implication seems to be that he is skillful at keeping his opponents at a distance, but if the opponents get close he's able to defeat them with close-up "body punches" too.