After the Moscow Currency Exchange was banned from using the dollar and euro for international trades, Russia really had big difficulties with payments under interstate agreements. Long before that, Russia tried to switch to using the Chinese yuan, but there were big difficulties with the yuan as well.
Therefore, Russia really wants to try to use cryptocurrency for these purposes. This is evidenced by the bill No. 341257-8 submitted to the State Duma, which allows the Central Bank to launch an experiment on September 1 to create a platform for using cryptocurrencies in international settlements. But Russia's main trading partners - China and India - generally have a negative attitude towards cryptocurrency and it is difficult to imagine how they will trade with it. Moreover, as we know, cryptocurrency has very high price volatility, which introduces a certain instability in settlements.
I don't know the real reason behind Russia's decision to use cryptocurrencies for international payments but as we can see , the war between the two countries is about to enter its 3rd year. That means Russia's international trade transactions have been going very well over the past 3 years even without cryptocurrencies. And in the last 3 years, I have never heard of trade deals between Russia and China, or India having difficulties. So why should they worry if China and India don't accept cryptocurrencies? You need to know that they work together to create mutual benefits for all three parties , no one party depends on the other . So it's okay if their commercial transactions don't use cryptocurrencies.
I think Russia added cryptocurrency as a payment method because they want to expand their market further. Many countries are still hesitant about US and NATO sanctions and using cryptocurrencies will avoid that . It can be said that it is just an alternative and they are fine without it , that is why they started thinking about it after 3 years .