In both Kenosha and Portland, as well as Charlottesville 2017 and every other instance (without exception) - Antifa are always the originators of the violence.
I suppose it depends on what you mean by "originator".
In the case of James Fields running his car into the mob and killing Heather Heyer, there was no indication of previous violence or threat. Unless you want to say that that incident "originated" before Fields got in the car, I don't think you have a case.
Also, in videos I have seen from Portland and Charlottesville, what I saw several examples of was a group of counterprotestors or left wing protestors blocking a street, and the right wing respond with violence. For example in Charlottesville, a counterprotestor crowd set up a shield wall to block the street, and I saw a group of pseudoNazis organize a charge and attempt to break the line. In Portland, a group of protesters blocked the street, and a right winger got out of his car and punched one of them. Those are kind of edge cases. The Trumpsters in Portland and the pseudoNazis in Charlottesville had a right to use those streets, but does blocking the street count as "initiating violence"?
As is common in lots of "he started it" situations so common among children and the childish, it's more commonly a series of escalations, making it difficult to say exactly who originated what.
Danielson came prepared to defend himself against the very well known, predictable violence he'd encounter from Antifa and was killed for trying to defend himself.
How'd that work out for him? I think he, and everyone else, would have been better off if he had left the weapons home. It looked to me like some of those Proud Boys or whoever they were were spoiling for a fight. They got it. Who won? Who is better off for it?
It's that "series of escalations" thing, and when it's all over two people were dead. So it goes.
Rittenhouse was also set upon by Antifa violence, and he successfully defended himself.
I haven't seen clear video of the first killing by Rittenhouse, or read a clear account of exactly what happened. I don't know that such an account exists that would enable us to make that judgement. In the case of the second killing, he was certainly being set upon by left wing demonstrators, but if the first killing was not in self defense, then the second killing was murder, regardless of self defense. I think more evidence is required to reach the judgement you have reached.
Whether it's the guy who got hit with a bike lock across the head by the Antifa professor a few years ago, or these events now - it's always the same story. These Antifa people, especially a dedicated core within them, openly advocate for violent measures and revel in the destruction of property, arson, and horrendous violence upon other persons - usually done in a completely out of the blue fashion like a "sucker punch" or ambush approach.
On this point, we agree. Antifa is a menace. However, one of the worst things that they do is rile up a bunch of idiots to oppose them. When it comes to the people engaging in the violence, there are no good people on either side.