Well, yes. But it could be literally anything. There are no criteria, no requirement for evidence, perception is all.
The alleged victim doesn't need to have said protected characteristic and it doesn't need to be the alleged victim who reports. It just needs for the act to be perceived as being motivated by 'hate' towards an assumed characteristic.
So anyone can anonymously report anyone else for any act, if they consider it motivated by hate.
'Isobel Gowdie gave a person in the street a dirty look motivated by racism/transphobia/ageism/ableism/sectarianism'
Police are duty bound to record and report that.
And as I've just read, police can ascertain a motivation even if the reporter doesn't.
I have to keep thinking it through myself, because it's so fucking mad.
Again, I'm not a lawyer or police, this is just what I can glean from the Bill and police guidance. I'd be very very happy to be told I'm wrong!