i am using gamekit ( https://github.com/gamekit-developers/gamekit/wiki/Blender-Addon ) there is no blenderplayer as you can see. can i change GPL license legally?
Gamekit is other Game engine totally different to the BGE. It has other license (I think MIT or ZLIB). The only thing in common is that it can load .blend files too. But, for example, it doesn’t use python.
What is displayed as the license is different to what actually is the license.
To change tue license legally you need the written permission of every developer who has contributed (ie you can’t).
However gamekit is MIT licensed - but does not use the BGE, so I believe you are not looking at the right file. What makes you think you are using gamekit? It’s a completely separate engine.
You are not allowed to change the licence (unless the licence allows you to do so). The GPL is very specific here:
You can change the licence information (the data) at the exe, but you still need to deliver the source and the GPL information. Be aware this does not change the licence on the software. You are not allowed to publish Blender/Blenderplayer under another incompatible licence.