Flashable zip will enable Google now integration & simple apk will not include Google now integration.
Flash Pixel-2-Launcher zip from TWRP (as system app)
Or install Pixel-2-Launcher apk as user app.
Any of following
Pixel 2 Launcher from Android Oreo 8.0
Pixel 2 Launcher from Android Oreo 8.1 DP1
Note: All features are working only in android oreo based ROMs. I tested all files in Nougat & Oreo based custom ROMs. Some users are reporting that app is crashing in marshmallow based ROMs. You need to give location permission manually to get weather data as launcher is not asking location permission but by default all permission are set off.
How to uninstall?
Flash Pixel-2-launcher-uninstaller (file from attachment) using TWRP or other custom recovery.
Magisk module of original Pixel 2 launcher for systemless installation is available here: