Arrow Any Z2 Or Xperia Rom for G2?

Why developers don't do this? I like Xperia Ui and apps. There are only Z2 Launcher with icons, Walkman and Z2 softkeys. But not system ui and framework.
LG G2 16Gb Black
ROM: Mahdi 2.7
Kernel: Dorimanx 5.8 AOSP
System Runtime: ART
Baseband Version: MSM8974A-AAAANAZM-1.0.190084
Build Number: KTU84P
Recovery: TWRP