In case you want good Lyney teams, one of his best teams is actually vaporize with Furina, Bennett, Kazuha/Xilonen

he's so fun to play with he's the best

Lyney can team up with Zhongli of course. But also losing his bonus damage from "3 pyro characters". Or replace Kazuha with Zhongli.
So zhongli + xiangling + bennet

To defeat multiple enemies better, Lyney need Kazuha. Also need DEHYA, to avoid interupt. Because Thoma and Xinyan shields are weak, and when the shield breached, Lyney can kicked out while doing Charge Atk

I have test my lvl 90 8/8/8 Lyney at domain in fontaine, also Vourukasha domain, and domain in Tsurumi island (every difficult domain with multiple enemies). So he is somehow weak at multiple targets, because CA mechanics

the summary is :

1. Charge Atk until lv2 to the enemy , that action also will add stack indicator for his explosion.
2. Detonate with ESkills

LYNEEYYYY

here before fontaine is released and ppl start whaling :)