If nothing else, they seem to be the douchebags defacing war memorials.
https://taskandpurpose.com/news/world-war-ii-memorial-vandal...
https://www.military.com/daily-news/2020/05/25/veterans-ange...
https://www.post-gazette.com/news/crime-courts/2020/05/25/Wa...
https://www.stripes.com/news/veterans/va-headquarters-vandal...
https://www.wcax.com/content/news/Veterans-memorial-monument...
A bit older:
https://www.kptv.com/news/3-arrested-vandalism-suspect-wante...
This is just a few links--there are many more. As far as I'm concerned, this is all you need to know about Antifa. You should make up your own mind, though.
2) Memorial Day: Unknown persons damaged two stones on a monument to Puerto Rican veterans for an unknown reason.
3) Memorial Day: Unknown persons painted an obscure reference to Peruvian communists on an unrelated WWI memorial.
4) This is the same news as (1).
5) May 4: Unknown persons tagged the wrong monument for not counting soldiers of color.
6) February 8: A counterdemonstration against a KKK rally (not mentioned as such in this Fox News article) found itself aimless when the Klan was intimidated by them into late-canceling, with some becoming restless and opportunistically tagging.
This is clearly a desperate search through Google News looking for any vandalism of war memorials other than the high profile reported ones you obviously had to make an effort to exclude (because you definitely didn't want to mention them now), blaming them all on "antifa" even where literally nothing is known about the vandals or their motives and concluding with "this is all you need to know."
But as to these not being "Antifa", get real. If any weren't done by Antifa, Antifa would nonetheless cheer the perpetrators on with great enthusiasm. That's what Antifa is about. They are denigrators and destroyers of that which is decent and noble in humankind.
...fascism, as per their name?
The KKK, as in your own link?
Or currently, multiple Confederate memorials[0] created specifically "to further a white supremacist future"[1], which you ever so gingerly avoided referencing directly?
[0]: https://www.usatoday.com/story/news/nation/2020/06/01/george...
[1]: https://www.npr.org/2017/08/20/544266880/confederate-statues...
Antifa has shit on the memory of these honorable warriors--many of whom gave their lives--by defacing their monument. For shame.