I looked up the name of the soldier, Sergey Yarashev, and I was met with a handful of sources, in both English and Russian, reporting on this. I also searched "hero of Russia", the name of the award allegedly received, and some of the first results were stories about Yarashev. Kremlin.ru and Izvestia (Известия), a government-owned website and a newspaper, are the two most popular sources reporting on this story. Credibility websites suggest that Russian media is under heavy influence from the Russian government and current administration and largely creates bias in Russian media. Additionally, Izvestia was recently acquired by a close friend of Vladimir Putin. (Kremlin.ru - MediaBiasFactCheck.com Izvestia - mediabiasfactcheck.com)
All of the sources cite an announcement made by Dmitry Peskov on March 10, 2026, for information about the Yarashev's award. Some sites list him as a Kremlin spokesman and others the presidential press secretary, which I assume is used interchangeably as Kremin is owned by the Russian government, but made me look twice. I can't find a transcript of the original announcement.
All things considered, I believe this claim to be true. The sources all report the same timeline and details, pointing to an official announcement from the Russian government. This may be due in part to the government's control over the media, but I don't think that is necessarily relevant because it is a military matter.
Disclaimer: I'm writing this only four days after it was asked, but, unfortunately, the original Bluesky post has already been deleted. I tried to investigate on the Russian Ministry of Defense's website, but it is blocked here in the U.S. I was also prevented from accessing certain parts of Izvestia and Kremlin.