One translation for crazy bitch in Spanish would be "perra loca".
This is a literal translation, loca meaning crazy and perra meaning bitch. (Note, the word order in Spanish is different than in English, so technically it is translated as "bitch crazy").
Another translation could be "puta loca".
I would be careful how you use these phrases, though. Where in English you might call someone a crazy bitch affectionately, if they were doing something funny, you cannot always directly translate some phrases into a different language and expect them to have the same meaning.
In Spanish, use of the word perra or puta can be highly offensive.
This is one of the problems of using something like Google Translate as a tool, rather than learning the language from native speakers.