Can I use other vinegar instead? I rarely find apple cider vinegar in Japan.

Yes, of course. In addition to the flavor "tang" boost, the primary reason for the vinegar addition is to boost the leavening power of the baking soda/powder to create a lighter, fluffier pancake.

You could certainly use a white vinegar or brown rice vinegar as mentioned above. I always have apple cider vinegar on hand, so that is what I use. I hope that you enjoy the pancakes and would love to hear how they turned out!

thank you so much for the answer. that is very helpful, I will try to do with brown rice vinegar!

You could use rice vinegar, even distilled white vinegar. I assume that the yogurt in the recipe plus the vinegar is to sour the milk, mostly for a tangy flavor. (You probably could get away with using water for the vinegar. Or, if you can get brown rice vinegar, that would be closer to the cider vinegar flavor.)