This cute pair of robots is a Lego MOC created by R 194. The two of them look very similar but they are actually very different. Almost like a deluxe model and a junior model. The heads are based on a 2×3 shape. The difference in their eye design is interesting. Both work well. The bigger model has one major upgraded feature compared to its smaller version. It has ears. The big robot also has improved arms with an elbow joint, and improved legs with knees. Another interesting detail that works well is that the big robot has a slightly different design for both its feet. It helps give is a bit more personality.
You can find more of this pair of robots over here: https://www.flickr.com/photos/163699374@N05/49966191396/