While on a Andrei Kanchelskis rabbit hole, I looked up the CIS and it lead me to this article from Futbolgrad about the team’s origins. Here’s the opening paragraph:
Between the time that the USSR national team qualified for Euro 1992 and the tournament began, the Soviet Union fell victim to the end of the Cold War. No longer able to withstand nationalist pressure and economic stagnation, by the end of 1991, the Soviet empire had dissolved into 15 separated independent republics. There was still a European championship to play, but no team left to play it. And yet, the awkward circumstances of no longer being a country did not prove to be an impediment to the participation of the Soviets at Euro 1992, albeit under a different name, leading to the curious but short-lived story of the national team of the Commonwealth of Independent States (CIS).
Once Russia became the main nation out of the USSR, those players had to make a choice: should I play for my home country or should I play for Russia? Most chose the latter, even though most were from Ukraine (including Kanchelskis who played for Russia until the end of his career despite being born in what is now known as Kropyvnytskyi).