If it's new, it's likely it will be under 9.2. If used.....can be anything.
If it's under 9.2, yes, you can downgrade. However, I recommend using pictures or even having a second 3DS open to help you unless you know how to read Japanese. There are NO other language options on a Japanese 3DS. (I own one).
Mine did not come with any games, but there are some free games on the eShop (you'll need to make an NNID to get them, and spoof firmware unless you can find working versions of them on your favorite rom site).
I bought mine used, and at the time there was not a solution for piracy, I mean "homebrew", that didn't involve buying a Gateway or Sky3DS, so I updated it. Mine also came with a free Dragon Quest game, which was cool except I have no clue what to do or how to play it. So mine mostly is used for that Badge center game and Pokemon Rumble World.