It may actually be a Legends thing. The thighs are hollow on the interior - pretty common feature of the main line. Also, it’s worth keeping in mind that Seige is clearly using some simplified elements from the earlier MP figures to do the carbots. They may be adopting a few bits and piece like older styled MP hands to make big characters. A few of the newer figures for that set are pretty wild, and because of repurposed MP parts and additional detail on the bodies, look pretty highly designed. The cab combining function looks pretty similar to the more recent Powermaster Optimus they did for measurements and fit - it’s conceivable this is Hasbro and TT using their existing resources to up the main line appeal to get some of that sweet sweet age group crossover going strong. Always remember, repurposing Mild elements and reusing and combining parts is a toy line’s best friend, and a tried and true Transformer-producing method. The more you know. Okay shit, the image won’t upload.