Pretenders are Transformers that have an outer 'shell' that they can use. originally, it was a flesh shell that was either human looking - but like 35' tall - or a monsterous creature for the Autobots and 'cons (as Hart said), but later Pretenders also had animal shells (the so-called Pretender Beasts), vehicles (the Pretender Vehicles), or even a shell that could transform and the Ultra Pretenders had two shells.
Alice was a 'tribute' to the Pretenders, but since she actually transformed from flesh and blood to a robot, she wasn't a Pretender per se.
It can be argued that Alice is much closer to the Japanese interpretation of Pretenders. Whereas in the US and Europe Pretenders had "outer shells" with a robot inside acting as an independent unit, in Japan the Pretenders were human sized and looked human in every way (down to civilian clothing) but when the needed to they would "become" the robot rather than split open and reveal one.