Yes, Igor Girkin (nomme de guerre Strelkov) is one of the four accused in the Dutch MH17 trial. As far as I can remember the case against him includes his being in command at the time and his VK account boasting bringing a plane down that day (I don't think any others were on 17 July 2014 as the Ukrainian air force had had a bad time, was depleted, and was saving resources). Nadiya Shavchenko, for instance, had been shot down and captured in June and was defiantly having her time in Russian custody.
He is being tried in absentia and has stated that the court has no competence to try him, the plane shouldn't have been there anyway, he didn't order the specific bringing down of the plane and someone else was posting in his name on VK as (this is where it gets truly strange) he was only posting on an antiques and reenactment linked site. However, at one point in 2020 he is reported on MoscowTimes as saying “In as much as I was the commander of the rebels and a participant in the conflict, I feel a moral responsibility for these deaths" though at other times his statements suggest otherwise [see image from an interview with Britain's own quisling Graham Phillips].
The verdict is apparently due on November 17th this year.
I don't pretend to have perfect recall, but at the time I saw (online, mostly on VK) the claim to have shot down a plane being flagged and pictures of the Buk being tracked (there were two candidate Buk launchers being followed in images and one was clearly the most likely), including by pro-Russian sources because they like doing that sort of thing, including analysing images to the Nth degree.
As the scale of the massacre became clear there were then swift denials while much of the world press went into a lagging discussion over what possibly could have happened. On the actual day those of us following the ATO already had a plausible explanation.