Interested to see what this is. Being in Japan,I'm sure you have pests that we don't get here in the U.S. and vice versa.
It definitely is not an aphid,whitefly,or lacewing(different veins on the wings).
Aphids travel on the wind, so they do have wings. There are so many types of them it is ridiculous. My issues are with black winged aphids,they get into young buds,and tight spaces in the new growth,makes it a pain to squish them. The green and red aphids I have had stayed mostly under the leaves or a random flower,much easier to squish.
Nice shot of the mantis...my only issue with them is,they don't discriminate. They kill more good bugs than bad.