Non-resident foreigner travelling through Russia to China

Hello, I am a British passport holder and will be travelling through Russia and would like to continue further to China. Due to the fact that I have been travelling for a longer period of time I was unable to apply for the Chinese visa in the UK as it would have expired before arriving in China.

I have no residence permit for Russia, but I do have reserved train tickets both entering and exiting China via Mongolia (where I no longer need one). I also have travel insurance and hotel bookings for the time I intend to stay in China.

I have been to China before on several occasions on tourist L, also obtained whilst travelling (obtained in neighbouring territories, such as Vietnam, Japan, Hong Kong and Mongolia), and I want to reconfirm whether I can apply in the same way in Russia (ideally in Moscow).

I would be grateful for your advice in this situation.

Erik.