(partial answer based on findings by this moment)
So was this clip shown as an advert on Rossiya 24?
The only truth seems to be that this clip was, indeed, produced for a Russian propaganda channel. The rest seems inaccurate, including that there is no confirmation if it was rolled on a propaganda TV at all.
Here's how the Russian "Lenta.ru" propaganda channel puts it:
It says that a Russian journalist Alisa Romanova worked on her 30-minute program "Bridal Diplomacy" (ru: "свадебная дипломатия") (YouTube video) for "Rossiya Live" propaganda channel back in June 2018. The topic was about telling stories of Russian women who married Chinese men.
"Lenta.ru" then confirms that the video in question was used by Romanova as a promo to the main work and it does not deny that the promo could have been shown on TV — probably, on the same "Rossiya Live" (not "Rossiya 24").
My personal opinion is that this seems plausible: a catchy, hype 20-second promo could attract the interest to the main work. Also, in 2018 the casualties among Russian men were not that significant, so the entire topic of women marrying Chinese men was not that sensitive to the populace as it is now.
Additionally, the video does not seem produced by Romanova herself. At least some of the "happy brides" in this promo video is produced by a Ukrainian (!) videographer Mykhailo Shestov.
For example, a fragment at 00:07-00:10 in the video showing a young lady wearing a checkered plaid blanket and chatting on a laptop is available for purchase here on ShutterStock.
and has some Russian words on the screen
It says Russian-Chinese relationship / a good choice / turns into a marriage (ru: российско-китайские отношения / удачный выбор / превращается в брак).