Indeed, it's flying.
The propulsion engine that can only enhance Champion Marquis' leaping ability on the alien planet's surface allows Champion Marquis to have flying capabilities in space. However, it's still far from the propulsion engine of the Emperor Armor deliberately shown to Ji Xinghe by Martial Emperor III. The Federation Science Academy's research into video footage determined that the propulsion engine used by that Emperor Armor is not a chemical fuel propulsion engine, which means that in terms of energy engines, the Empire is actually ahead of the Federation.
