If this is a genuine question: You'd short a Canadian "Total Stock Market" fund like (VCN) Vanguard FTSE Canada All Cap Index ETF. You can also short the currency, but that requires some expertise since you need to consider the relative currency you purchased from too.

You can short the Kraft Dinner manufacturer and invest in New England maple syrup futures.

Forex

Not enough pip movement.

Yeah but Forex you have to balance the BOC moves and the Fed.

That said if you think Canada is going south economically faster then the US and inflation is going to temper than the rates will go down faster and the dollar will be lower vs USD.

Have babies

Trudeau's gone in a month so be careful with the volatility. Mark Carney coming in as replacement.

Has this rumour finally gone mainstream?

Not a rumour, it's happening in plain sight. Why would Trudeau call that Toronto byelection end of June? He had plenty of time. He called it in June because the latest he could step down was July in order to have time for a leadership race before the next election. The reason the byelection will precipitate his resignation is it will be a bellweather performance in a traditional liberal stronghold, which will almost certainly show vast liberal underperformance leading to Trudeau's resignation. Among the factors are Trudeau's plummeting approval rates that are stuck very low, Liberal polling currently near 20%, far below the conservatives, also this riding is the 5th most populous riding for Jewish votes in Canada, who from what I understand are none too happy with Trudeau's stance on what's happening in Gaza. So it's less a rumour than a foregone conclusion, in my opinion.