How to start game with new character without shared stash?

In Diablo 3 I have a hero with lots of gold, items and whatnot. How do I start fresh with the other hero?

When I created a new character (on the same battle.net account) I had access to the stash and gold of the older hero.

Is it even possible to unlink that connection?

It's called Season. Those run for a few months and are then "reset". Each Season you start completely from scratch. New character, no stash, no gold, etc.

Outside Season, the only option I can think of is to switch from softcore to hardcore. Characters in Hardcore will share a stash and gold, but it will not be shared between softcore/hardcore.

So to summarize:

• Each season offers a start from scratch (though only once per season again)

• Switching to hardcore offers a start from scratch (only once for a lifetime)

• A season offers a fresh start for softcore as well as hardcore -> 2 fresh starts per season

The next season (season 16) starts on the 18th January 2019