Zhongli and Childe are good friends and Kaeya and Diluc are Sworn Brothers. However, they have not met as in a group. They are from different regions, with Kaeya and Diluc being from Mondstadt, though Kaeya formerly in Khaenri'ah, Zhongli in Liyue, and Childe in Snezhnaya. So it's mostly rare for them to meet all in, as a group.
The 4 are far different, as far from their color schemes. Kaeya and Diluc are very different due to Kaeya being associated with blue while Diluc is associated with red. Though Zhongli and Childe don't have color schemes that are too different as Zhongli is associated with brown while Childe is associated with orange because of their hair colors. Their color schemes are based on the color of their vision/gnosis. They have different voices, within Diluc and Zhongli seemingly have somewhat, deep voices. And for Kaeya and Childe, having a somewhat, similar voices.
The 4 have different personalities that are quite, fitting for them. Both, Childe and Kaeya are both teasing with their personalities. Meanwhile, Diluc having a cold personality and Zhongli having a calm and polite personality. They also are considered to be very attractive to the Genshin Impact fandom because of their appearances, voices, personality, and more.
DCKZ is very popular within the Genshin Impact fandom, with the four being the most popular Genshin Impact male characters within the fandom. They're known for being the four 'husbandos' as well within the fandom. They're seen to be the most attractive genshin male characters known in the Genshin Impact fandom, they have lots of fans, having a huge fanbase, because of their attractiveness.
In a Band AU, they're called as DCKZ since the "D" stands for Diluc, "C" stands for Childe, "K" stands for Kaeya, and "Z" stands for Zhongli. They're also seemed relatively popular as there's already a tag for it. They're also popular along side with the 4NEMO band. However, they're mostly popular as a friendship to be exact.
This can also be a double date, respectively, ChiLi and KaeLuc. Considering that they're both, the most popular ships and have the most written works on AO3, within the Genshin Impact fandom. However, there are also alternatives such as, Zhongluc with Chaeya and ZhongKae with Chiluc. The four are the most written characters on AO3, their respective ships are also the most written ships on AO3.
- Chaeya refers to the ship between Tartaglia and Kaeya
- Chiluc refers to the ship between Tartaglia and Diluc
- ChiLi refers to the ship between Tartaglia and Zhongli
- KaeLuc refers to the ship between Kaeya and Diluc
- ZhongChaeya refers to the ship between Zhongli, Tartaglia, and Kaeya
- ZhongChiluc refers to ship between Zhongli, Tartaglia, and Diluc Ragnvindr
- ZhongKae refers to the ship between Zhongli and Kaeya
- Zhongluc refers to the ship between Zhongli and Diluc