Nikyoji Kurono's time-stop ability was extremely destructive against inanimate objects without magic power. For example, she only needed one shot to destroy one of America's aircraft carriers, using time to make it decay. However, this only applied to inanimate objects without magic power. It was not nearly as effective against the American Commander's spiritual-armament warship.
Theoretically, given enough time, Nikyoji Kurono could have destroyed all of America's warships. However, the American Commander was no mere decoration. He might not have been able to stop Nikyoji Kurono, but his spiritual-armament warship's main cannon was immensely powerful, capable of destroying an entire town with a single shot. If Nikyoji Kurono went to destroy the other warships, she would have no way to stop the Commander from firing his main cannon. Thus, neither of them dared let their attention wander during their standoff.
Meanwhile, Saikyo Nene's Blade Art, Overlord Celestial Star, was a skill capable of dominating a battlefield. It was especially effective at sea, where she did not need to fear collateral damage to her own country's mainland. However, America was not stupid. They dispatched nearly fifty Superhumans to suppress her. America's special superpower unit was composed entirely of Superhumans. Although mass-produced Superhumans were inferior to those painstakingly cultivated, their numbers were enough to make up the difference. America had sent nearly two hundred Superhumans this time.
More accurately, The Great Professor had deployed the entire active-duty special superpower unit in order to obtain Stella.
Besides Saikyo Nene, Stella and Kurogane Ikki joined forces to hold back dozens of Superhumans. Together with the other magic knights, they temporarily stopped America's fleet out at sea. However, although the two sides had reached a stalemate, the ordinary soldiers had suffered grievous losses.
America's warships had to defend against meteors falling from the sky, as