"It boasts a revolutionary fixed-barrel-under-the-guide-rod configuration, resulting in less recoil felt by the operator."That's super revolutionary. It's so revolutionary that John Browning's very first commercially successful autopistol used it a hundred and seventeen years ago.
But it looks like the PKO-45 is more of a copy of the Bayard 1908, itself something of a riff on the M1899/1900 Browning.
(H/T to Unc.)