So obviously, since it they both share yellow plating, and black joints, Bumblebee was based on the Eva. Although looking to Japanese mechs for influence when designing something is common, especially if you're working on Transformers, don't just assume they saw one thing and went with it, more of a agalmation of ideas ranging from the original Bumblebee to Japanese mechs.
Also, for the record. I've never seen Evangelion all the way through, because the whole "lets make angels into robots to fight angels" premise, is well, stupid. That and the series bored me to tears.