Gargamuni, while naming Krishna, mentions that there are four types of complexions incarnations have:
शुक्लरक्तस्तथा पीत इदानीं कृष्णतां गतः।
The while coloured one could be the Hari who was related with the Gajendramoksha and incarnated in the Satya yuga, as He is referred to as शुक्लाम्वरधरं विष्णुं शशिवर्णं चतुर्भुजम्।
According to the Gaudiya Vaishnavas, Mahaprabhu Sri Chaitanya is the yellow-complexioned one, though the major Vaishnava sects dont accept this. Mahaprabhu of course could very well be the yellow-coloured complexioned. But then the red-coloured one becomes the incarnation of the Treta yuga. Who is He? And, who is this yellow-coloured incarnation according to other Vaishnava sects?