I'm considering reversing the hemisphere, so the equator is to the north. Southern Rokugan is cold, and northern Rokugan (with the exception of mountain tops) is warm.
Large sections of Unicorn lands are desert, there's occasional savanna in Lion territory (as is inexplicably the case in canon Rokugan, presumably to explain the presence of actual lions), Mantis island climate is more Iceland than Okinawa, Dragon has pockets of tropical heat in valleys, with temperate-to-cold peaks.
On the other hand, considering it's all supposed to be covered in deep snow in winter, maybe it's better to discard realistic climate entirely and just assume everywhere is really hot in summer and really cold in winter.
Either way, here are some notable cities:
Capital of Peace / Capital City / the Imperial Capital (Otosan Uchi)
A city more defined by craftsmanship than trade - many of the Empire's finest artisans compete for the honour of plying their trade in the Capital. Defined by a distinctly upper aristocratic culture, as influenced by the proximity of the Emperor. A Mekka for many High Skills. "Necessary evils" - waste management, executions, prostitution, trade (of things you did not make) - are relegated to the furthest edges of town, usually outside the city walls. Permanent artisan-run shops are accepted in the city proper, but getting a permit is difficult.
Ranbo City / Ranbo / City of Drink (Toshi Ranbo)
Known primarily for "Ranbo" - an ancient variety of "white spirit", a type of alcoholic drink similar in strength and feel to vodka. Loved by locals and connoisseurs and made famous by the many Kakita Artisans who've settled in the city and composed miles of verse in honour of the drink.
- Alcohol ceremony still more common than tea ceremony
- Decent "second choice" for artisans that don't establish themselves in the Capital
- Commercial hub of east Rokugan, picking up a lot of the business that would've taken place in the Capital had it not been so openly disdainful of merchants
- Stark, conservative architecture
City of Sacrifice / Isawa's City / Gisei Toshi
Secret city of the Phoenix. An extreme student town shrouded in secrecy - no commerce to speak of, not a lot of outsiders, almost everyone you meet is in someway involved with the Isawa shugenja school.
City of the Rich Frog / City of Heaven's Judgement / City of Foreigners
Built towards the end of the Lion-Unicorn war and functions as a gateway in and out of Rokugan proper. The third name is only relevant if the Unicorn eventually lose, in which case it becomes the only city in the Empire that is open to foreign merchants, which primarily arrive through the desert between the northwestern mountains deep in Unicorn lands. The Second name may be used if they are defeated by the Lion specifically (as opposed to the Hantei restoration), which results in Unicorn exile from the Empire and them being included in the "foreigners" who are only allowed to enter Rokugan through the city.
Either way, it is the only city that sees a decent amount of Dragon(/Dragonfly) presence, which, combined with the prevalence of foreigners, and the ever-present Unicorn-Lion tension, gives the city a strange vibe. Most Rokugani experience it as extremely exotic.
Journey's End / Greenwall / City of Lies (Ryoko Owari)
The city most affected by the result of the Unicorn's invasion of Rokugan.
- if the Unicorn remain in charge, and the city is still de Facto Capital of the Empire. The previous Capital retains its name, but little of its political significance.
- if the Lion exile the Unicorn and the Hantei restoration fails the Shogunate takes control of the city, likely leaves the day-to-day running of most of the northwestern former Scorpion lands to the Ikoma.
- if the Scorpion survive the war and hold the city (either the restoration succeeds, or blame is successfully deflected after it fails) the Scorpion come to embrace many of its Unicorn-era quirks, including merchant culture, the booming drug trade, its criminal gangs, its unapologetic hedonism. In the post-war era it becomes a favourite gathering place for a hip new breed of romantic upper class youth.