https://www.pcgamer.com/monster-hunter-world-is-coming-to-final-fantasy-14-in-a-new-crossover-this-summer/

Final Fantasy 14 is getting some new dragons to fight this summer thanks to Monster Hunter: World, which, as Square Enix announced today during its E3 2018 presentation, will lend at least one of its monsters to the MMO in an upcoming crossover. 

We know the crossover is due sometime this summer, but Square Enix didn't say much else. That said, there's plenty to speculate on. Rathalos, a big red dragon and the longstanding face of Monster Hunter, was the headlining act of the announcement. Which is neat, and also makes me wonder if Rathian, Rathalos' female counterpart, or indeed any other Monster Hunter: World monsters, will make an appearance.