If you ask the question, who benefits, the answer is definitely not Ukraine. Why would the Ukrainians send arms to a NATO member that is an ally to sew civil chaos? If the Muslim and black rioters topple the French government, it would be aligned with the Chinese Russian Iranian axis. If a Napoleon arose from the French Army and seized control, there might be a rightist government which, like Hungary and Italy, that would want to end the Russian Ukrainian War on terms which would ensure the loss of the Eastern areas seized by Russia.
Ukraine never benefitted from its relationship with the USA and NATO. In 2013, it had a whole, and peaceful country. It had Crimea. It has Russian-speakers and Ukrainian-Speakers voting together to elect Presidents. Its citizens wanted closer relations with the EU, for trade, but also - so they could emmigrate. There was NEVER support for war or confrontation with Russia. Even Zelensky was elected on a "peace platform."
Sadly, the Maidan coup gave them war. In a very classic move, the US/NATO empowered and pushed forward a very fringe, radical group of ultra-nationalists and neo-nazis, who would prepare the stage for conflict with Russia. Who benefitted? Neocon ideologues in Washington DC.
And since then, Ukraine has lost Crimea, it has lost the east, it has lost 30% of its population, and it lost a generation of young men.
I’d be more inclined to believe the Taliban is routing some of our “abandoned” weaponry into France.
There are several possibilities as to ow the French rioters are obtaining guns. I don’t know enough about the French military to know if they have leaders who would push Macron as they crush the rioters. If it is like ours, the flag officers are Depp State acolytes. Macron has made sounds about closer relations with the BRICS nations. It is possible American and British sources are providing the weapons to undercut the French regime
In a black market the sellers are agnostic and the buyers are anonymous. Greed is the motivating factor and any corrupt Ukrainian could be repsonsible.
There is a whole separate conversation to be had about "who benefits" from a little chaos in France right now.
Why? For $ of course. Plenty of people screw their own country for cash. Joe Biden and Bill Clinton come to mind.