Specialized made the "Trivent Terra" which was essentially the Trivent upper with MTB sole on it, for a few years. Then they stopped production beause the 50 or so people in the world who wanted them bought them, although some deep eBaying and Googling might be able to find you a pair from another country or something. I know I had to Western Union transfer money to some German website on the 15th page of Google Shopping to find them in my size, and I only wear them for races in the hopes that I can keep them for my whole racing career.
That's probably what you're seeing outside of maybe a very small handful of athletes in the world that might be able to get them to make a custom one-off (like I recall seeing Pearl Izumi did for Flora Duffy).

If you can't find the Specialized one on Google/eBay, you may have luck as Sidi and Gaerne have also each made a MTB tri shoe at one point.

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IG: idking90

Don't know about Trivent Mountain shoes, but I do know that Luck makes a version of their triathlon shoe with a "MTB" sole.


http://luck-bike.es/en/98-tri-mtb

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"They're made of latex, not nitroglycerin"

Cool, thanks guys. It was definitely a new version on the shoe, but given it was used by Ruben Ruzafa and a few other top guys they have probably made them to order and not for public sale unfortunately.