Certainly not cicada killers--those have yellow stripes on them, are considerably larger, and also have a very different shape of abdomen. They certainly look to have a hymenopteran "waist" so that means they aren't termites, they are some kind of winged ant. Possibly carpenter ants due to the large size (for ants) and the reddish-brown color.
@Alex's answer found a very close match with Pseudothemis jorina but as pointed out there that species is generally found in Southeast Asia, not Taiwan or Mainland China.
Pasting Pseudothemis jorina in the species search box in https://www.inaturalist.org/observations (found in this answer to Identify this large, beige or pine cone-colored squareish beetle ...
The closest match I can find is Pseudothemis jorina:
It's very similar to your pictures in regards of body shape and the light distinct band, although I'm not sure it would normally be found in Taiwan. It's more common further south like Thailand and Malaysia.
Looks like Bagrada hilaris commonly known as bagrada bug or painted bug. It is native to Africa but is also found in other countries.
It is a major pest for crops especially cabbage family.
Large no. of bugs congregate on the plant and cause extensive damage.
Looks like this species is Orthetrum triangulare commonly known as blue-tailed forest hawk.
It is an Asian fresh water dragon fly species.
As you mentioned that the dragonfly had a bluish hue, it became clear.
Since a similar type of this, called Orthetrum albistylum commonly known as black-tailed skimmer is found in Central and South Europe to China and ...
It has been known for 40 years or more that some insects such as termites digest cellulose by synthesizing their own cellulases, whereas others have a symbiotic relationship with gut micro-organisms that perform this digestion (see Martin, Comp. Biochem. Physiol. (1983) 75A 313-324 — requires subscription — or this short popular science article).
What is ...
It seems to be a Yellow-banded polybia wasp (Polybia occidentalis), a species of Potter wasp.
my doubts with this conclusion is that the abdomen of the insect in your photo is quite large compared to other observations of the species. Also, Polybia occidentalis is a species that exists in South and Central America, not up north in New York, Perhaps it is ...
This is probably because the color in dragon fly wing is due to chitin crystal and which is protected by some secretion over the entire wing something like cuticle upon leaves and when dragon fly dies that secreted substance upon wing washes away when not maintained resulting in shredding off of the color from wing. Sorry I can't comment (<50 reputation) ...
Those look to me like fungus gnats. If you're looking to get rid of them, I've heard that putting a layer of rice hulls on top of the soil keeps them from reproducing. From what little I've read my identification doesn't go much deeper than superfamily, taxonomically, but it's a least a common name to work from.
It could be Pyralis farinalis, the meal moth. It is a cosmopolitan moth of the family Pyralidae. Its larvae are pests of certain stored foods, namely milled plant products. I don't think it's adults feed as they do not live long after mating.
Here is a link to its Wikipedia article:Pyralis farinalis
One notorious pest of potato plants are cutworms. Unfortunately due to the the discoloration of the species I am not able to identify for sure which species of cutworm it is.
Cutworms attack a wide host of plants (more info here). According to that same website, the main ways to avoid the damage these larvae can cause are to:
Remove all plant residue from ...