WWE Heavily Promoting Interesting Royal Rumble Stipulation; 2019 Winners Potentially Switching Brands?

As we head into 2019 and the annual WWE Royal Rumble pay-per-view, one stipulation the company seems to be heavily promoting is the long-time clause that allows a Rumble winner to choose which championship they challenge for in the main event of WrestleMania, regardless of which brand they belong to.
This isn’t exactly a new concept, as WWE has teased its stars changing brands in the past in order to set up potential world title rivalries, although no one has ever actually made the jump.
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