Franklin Foer in Slate, Josh Marshall, and major tweet endorsements of the foregoing including from Paul Krugman.
While there's lot of tantalizing 3 degrees of separation stuff, the entire edifice has one huge weak point: it rests heavily on Trump adviser Paul Manafort's time as a consultant to former Ukrainian president Viktor Yanukovych. However, Ukrainian politics does not lend itself to picking one strand and extrapolating from that: the strands are tightly woven and there's always more than meets the eye.
One sign that something is amiss is that both Foer and Marshall dump a huge number of names into their articles but neither mention Rinat Akhmetov. Why does that matter? Because by the same accounts on which they're relying for their theories, it was actually Akhmetov who first hired Manafort, not Putin or Yanukovych. That's an especially glaring omission for Foer, who has a book titled "How Football Explains the World" to his name -- Akhmetov is among other things the owner of Shakhtar Donestsk football club (crest above).
And, as this Euromaidan article explains, Putin and Akhmetov certainly have overlapping but hardly identical interests, an agenda around keeping eastern Ukraine profitable for Akhmetov while not costing the Russians too much money -- by which standard, events have already spiralled too far for both of them.
Remember finally that the new theories are resting on Manafort's 5-10 year old stint in Ukraine, when circumstances have since changed dramatically. Of course the great thing about Russian intrigue is the way it blurs the line between possibility and fiction. Maybe some people are taking TV shows a bit too seriously.