This is an interesting figure revealed recently via a catalog scan tweeted by someone who attended the recent UK Toy Fair. The report described by Full Metal Hero seemed to resonate along with this finding.
Behold, Transformers Prime Optimus Maximus who looks like a crossover between OTFCC Sentinel Maximus and Primal Prime of Beast Machine (look at that feet!)
It was learned that the figure will be a Cyberverse figure where it will be a Cyberverse base like playsets that is able to transform from a figure to a base and vice versa.
In the image that has been revealed, it shows that Optimus got an upgrade with new parts and weapons, including firing missiles!