This is true - and certainly, there *were* firm believers in the Greater East Asian Co-Prosperity Sphere. Take, for instance, the IJA soldiers who stayed behind in Vietnam to fight alongside the Viet Minh against the French! But the concept was *far* more racialized than US equivalents.
Jeremy SalkeldThe extent of both Taiwanese and Korean willing participation in the Japanese imperial project, with the implicit hope of securing greater status in a postwar order, gets obscured a bit by the abject failure of the Japanese war effort and the nationalist turn in both polities.