Probably Andrew Scheer with around 52-53%, but that is on caveat that run on same platform. Scheer being in US would probably run on a much more right wing than he did. For example he would probably promise to outlaw abortion or severely restrict it which would be political suicide in Canada. Trudeau by contrast would probably be more centrist and not as left wing as he has been in Canada.
Screer with his stances now would be a moderate Democrat or maybe a liberal Republican, Trudeau would definitely be on the more left wing of the Democrats, I’d say Screer wins a lot more with his stances as they are. The reason the GOP struggles is bc they have toxic branding not because there’s a lack of “center right” voters.