A way working for version 1.3:
http://forum.paradoxplaza.com/forum/showthread.php?737767
Every province you cede in a peace deal will reduce your AE with every nation
in the world by 15.
Every nation you release from your nation in a peace deal will reduce your AE
with every nation in the world by 30, regardless of that nation's size
Every nation that you end the vassalisation of in a peace deal will reduce
your AE with every nation by 15.
The most interesting part of this is that ceding provinces which don't even
belong to you still reduces your AE
所以:
1.养个附庸，喂地给它
2.等附庸把被喂的地造核心之后
宣随便哪个小国，在peace deal中让附庸把地还给原主人
3.宣原主人，逼原主人还地给附庸
Then repeat 2&3
有时在peace deal中对方对于你的投降条件并不感兴趣
但没关系...把对方揍到100%，这样子它就会接受了
另外，放附庸国会减少AE，但减少的量并不多
但1.13版吞附庸国不会增加AE，所以你可以放了再吞，吞了再放
1.3版就不能了。