I mean, it was kind of obvious when we saw her. If there's already two deadly sins mentioned, and someone shows up with similarities to one of them, the other sins are probably out there as either people or weapons too. People were calling that stuff before she or the sword had even showed up too. Deadly sins are sort of a package deal in some form or another generally. If she hadn't declared herself as Wrath now, I'd have been wondering if the MC was going to collect all the sins himself since his sword was Greed.