Japan

https://friouk.com/ This is a good link, I can't help with time zone's, but I'm sure someone will be along to help, have a wonderful time in Japan, how exciting

@kzlorenz, I am jealous - Japan is one of my dream locations.

The frio bags @Robinredbreast provided a link to is the usual mechanism to keep your insulin cool whilst you are out and about. I have taken mine to India, Ghana, Venezuela, Barabados, ... and my insulin has been unaffected in any of my travels.
The way they work is to soak them in water which is absorbed by some crystals which turn into gel. Some over-zealous airport security guys may be sensitive to the gel. Therefore, I wait until I arrive at my hotel before soaking.

My usual approach for adjusting basal for the time difference is to take it at between 22 and 26 hour intervals. This allows you to gradually adjust the time you take it until it is at a convenient time.

The usual recommendations for travel are
- take twice as much kit as you think you need
- keep it in your hand luggage when you travel
- take a letter from your doctor explaining that you need to take sharps with you
- keep your insulin cool and test meter out of the sun

Have an amazing time.

We went to Japan for a couple weeks in 2014 and I just brought the usual supply of insulins and didn't refrigerate it at all. I just did my basal in the morning and didn't adjust for time zone. You might consider an extra pen in case it malfunctions. Once I take the pen out I don't put it back in the fridge. Some might however. I have a cooling thingy for if I have to leave it in a hot car however.