What is Britain had not entered WWII

[ReluctantSamurai]

Because of admiration for England just like Germany

One does not spend millions of yen to build the finest fleet in the world, at the time, for admiration. Power in the PTO means you need to have a strong maritime navy in order to "swing the big stick". Given Japan's desire to exert their influence, their dominance, in SE Asia and beyond, they saw what the US and Britain were doing in terms of ship-building and took countermeasures...their own "big stick".

it has to be pointed out that they behaved no better than any other colonizing nation including death camps where in average 20% died

No country has ever been immune to such behavior.

Even more reason for Japan to strive for a Greater East Asia Co-Prosperity Sphere...

little did anyone know that the Japanese would be far, far worse...