Russia has many options that can be used to avoid sanctions. Using any payment method other than the dollar would be appropriate, and then we would find that local currencies or exchanges for oil/food would be more effective than the dollar.
Bitcoin may be an option, but I do not see that there is anything special about Bitcoin that will make the government adopt it.
The effect will be for individuals to buy Bitcoin, changes will happen, especially if governments decide to impose restrictions on deposit withdrawals or at least the currency depreciation.
I agree with your point, as they're accounting for 17% of the world's natural gas and 12% of its oil if they go for other local currencies in exchange there might be a chance to avoid sanctions.
But I don't think Bitcoin would an option because as they're dealing in a huge scale they'll prefer stable currencies, because they cannot do a sudden shift to bitcoin as it is very volatile!
They can legalize crypto by introducing their own crypto in to the market and imposing tax on other crypto currencies like how India did recently.