(You can get a room with a window, but for an overnight trip it seemed a bit pointless.)
I find it difficult to sleep on sleeper trains, and usually arrive tired at the destination. Where there is the option I will use a night train out of principle (it's still usually more comfortable than a plane) but, if I have time, a daytime rail journey is much nicer.
Eye mask, you want the kind that looks like a bra and puts no pressure on your eyes. "Nidra" is the brand I usually get, they're cheap, I replace mine regularly.
Noise canceling headphones. I go for cheap sets but get what works for you, something wireless. I have found history podcasts and music both work well for me.
I have a neck pillow that basically looks like a cervical collar and is made from memory foam. Works really well for me but was pretty expensive, and it takes up a bunch of space so it's a tradeoff to consider. And wear a zipped sweatshirt on the plane, use it as a blanket - after turning the air vent on max.
Any particular you know that in fact do cancel noise and really work?
On the other hand, a $400 set of Sony's will basically put you in audio isolation - to the point that some people genuinely don't like them. A friend had me put his pair on in the middle of a busy restaurant at lunch time and I'm not kidding when I say it felt pin drop quiet.
My Airpods Pro are great but they only have a battery life of 4-5 hours per charge (20 hours in case, but you have to wake up to charge them).
My Bose QC 15 over ear headphones can stay on much longer (> 20 hours of battery life) and have great noise cancellation, but as soon as I lean my head to either of the side headrests on the seat, the noise cancellation "leaks". I've never been able to sleep on a plane with my Bose QCs.
The best solution I've found so far have been plain-old ear plugs ($5).
Since they're cabled to an external battery box they can easily last through any flight, and you can leave the USB charge cable connected to an in-flight power socket while you use them to keep the battery full.
And Aeroflot are not known for their hospitality and understanding to foreign travelers...