Great news for LG G4 owners! XDA Senior Member tabp0le posted a guide on how to get Xposed working on the LG G4. All you need is root, no unlocked bootloader required. The method involves installing the arm64 version of the framework by flashing it through Flashfire, and then getting the Official Xposed Installer (through the APK) on your device. Read the thread carefully before installing.
tabp0le‘s thread contains a step-by-step guide on how to get it running on your LG G4. Many users have reported that the installation process was successful, but it does take a long time where the device remains unresponsive. Here is a list (from the thread) of devices that have been tested and confirmed to work with this method:
Follow every step listed in the thread carefully and at your own risk. Make sure to read the entirety of the thread to gather all user reports and feedback before going ahead. The procedure is simple, but given this is a potentially dangerous tweak, one must always proceed carefully.