It won't be available in the future. If you scroll through the website for the battlepass, it is listed under "battlepass exclusives" and it is even mentioned that "This item will never be tradeable or marketable. Unlock it bevor the International ends." This does not mean that Valve won't re-release it in a reworked way (s. "promise of the eminent renewal" from 2018 battlepass) though. In theory the item is still obtainable by being gifted, if you have a friend that willingly parts with it or go for some sort of gift trading or something.

Since this is the first new "persona" added to the game, we can probably expect others though. It might be for other heroes though and Valve being Valve they might just abandon this new "persona" concept like they abandoned other item concepts completely (e.g. "ancient" items).

Good luck, I hope you get your annoying toddler Carl