And you think Tyson and Klit are examples of fighters with great lateral movement? Watch Ali fight Williams. THATS lateral movement.
Can't believe only one person named Sugar Ray Leonard (versus Davey Boy Green): https://streamable.com/dcor
What I've seen of Tunney on the films is that Gene was equally fluent moving left and right, on both offense and defense. Champ Thomas slammed Ali for only circling left, clockwise, and Foreman's whole strategy in Kinshasa was predicated on taking that step to the left to head him off. Muhammad's most extended and dedicated effort at moving counterclockwise was with Mildenberger, and he didn't look as comfortable doing it as Larry Holmes later did in Shavers I. (When it came to moving clockwise, the Assassin was the most fluid of the orthodox HW Champions.) Foreman versus 1960's Ali might've been interesting. Muhammad was flying around the ring at that time against guys like Liston, Patterson and London, but it was mostly to the left until southpaw Mildenberger. Does George force him to engage with his ring cutting step to the right, or can the young Ali evade him for 15 rounds or wear him down first? Joey Archer and Joey Giardello are names I like to bring up. So's Miguel Canto. I tend to lean towards Tunney, because his late career strength and power meant he could advance as well as retreat. Tommy Gibbons discovered that having Gene come forward on him wasn't a great situation, and whether one tried moving left or right to get away from Tunney, Gene would shadow them with matching pressure. Guys like Pep and Robinson are going to be automatic mentions, so my inclination is to dig a little bit more.
It's an instructive question. Frazier-Cummings might provide one example not widely considered. When Layne took on Marciano, Rex banked everything on being able to bull Rocky backwards and take away his punching power, but Marciano planted himself and stood his ground in his best filmed demonstration of physical strength. Frazier was not Marciano, and when opponents like Chuvalo or Stander tried to stand their ground or force him into retreat, Joe side stepped, moved around them, and chopped them up. Jumbo Cummings, being the foremost weight trained bodybuilder in boxing during the early 1980's, banked everything on replicating the freakish Foreman's template on Smoke, forcing Joe back with the combination of height, weight and cut resistance Stander and Chuvalo didn't share. (Stander was shorter than Joe, Chuvalo was 6'0" tall with a shorter reach than Frazier. But Jumbo was closer to Foreman at 6'2"-3" 225, and figured his combination of strength and stature could likewise do the job on an aging and mothballed Smoke.) It didn't work out the way Cummings had planned. As Jumbo attempted to bull Frazier back and away, Joe thwarted those efforts with quick side steps, leaving Cummings within his punching range. Floyd discovered size and physical strength weren't enough to stop Frazier, that punching power was also essential to that equation, and Foreman had force of impact Jumbo didn't share. Bull vs Matador was actually how Cummings look against Frazier at times, with Jumbo taking a bolt forward and Joe quickly taking a step aside. In a literal context, what Smoke was doing could be qualified as lateral movement. As contrast, Locche used virtually no lateral movement in his dismantling of one punch knockout specialist Fuji. Paul had won his championship by blasting out a legitimate stylishly fencing cutie in Sandro Lopopolo, but Nicolino used his legs so little in dethroning Fuji that the number of steps he took could actually be counted. Want to mention Nel Tarleton as a guy I like with respect to lateral movement and classy fencing. There's also footage of Nella aggressively whaling away at the body to produce knockdowns, but he was primarily a stylist according to most extant footage. I've long advocated for his induction into the IBHOF, and fairly confident that Tarleton can eventually gain entry to Canastota if Len Harvey could qualify.