Building on the earlier suggestion, I actually had a pretty disappointing time with the expensive L-series glass. Spending a fortune on the Canon RF 24-70mm f/2.8 L IS USM was a mistake because it felt too heavy and stressful. If you want to save money:

• Try the Canon RF 24-240mm f/4-6.3 IS USM
• Its cheaper and covers every situation
• You wont be terrified of dropping it Honestly, save the cash for the actual trip!

Congrats on the R5II, thats a wild camera for a first timer! Unfortunately, buying the body is only half the battle... the lens prices are honestly a gut punch. I initially tried to save money with the Canon RF 24-105mm f/4-7.1 IS STM but I was pretty disappointed with it. It struggled so much in low light when I was walking around at night, and the image quality just wasnt as good as I expected for such a high-end sensor. If you want one lens that actually does justice to that camera while you are in Japan, you really gotta get the Canon RF 24-105mm f/4L IS USM. Its pricey, but it stays at f/4 the whole time and is built like a tank. It basically never leaves my camera now because it handles everything from wide landscapes to street shots.

I saw this post earlier but just getting a chance to chime in now. Since you are heading to Japan, you are gonna be walking miles every day, so you gotta be careful with the weight of your gear. That R5II is a beast, so you really dont want to put a cheap lens on it or you are basically wasting that expensive sensor. I would suggest looking at the Canon RF 24-105mm f/4L IS USM. It is the safest all-rounder because it is built like a tank and has great range for street photography. The f/4 aperture might be a bit slow for dark alleys in Shinjuku, but the stabilization is rock solid. If you want the absolute best low-light performance, the Canon RF 24-70mm f/2.8L IS USM is the gold standard, though it is way heavier and you lose that extra zoom reach. I would stick with the 24-105L for a first trip, honestly. Just make sure to get a comfy strap!