The Seven Heroes and Five Righteousness version of "The Boy Here" also features characters from a friend's work.
List of friendly guest characters:
Zhao Zishan - from "Tianyuan" BY Jin Tong (Jin Xiangyu)
Song Qi - from "Origin" BY Tianjie Xiaoyu
Ye Chaofeng - from the series "Block" and "Broken Formation" BY Clare, Min Ye
It's a trap, and the author doesn't really want to fill it in anymore.