I installed the Wings XDA 968 fonts-Oreo apk today. I got tired of redoing everything every time I rebooted my phone and just went with the adb fastboot version. I can live with duplicate fonts in my list just as long as they work. My current font of choice is Sharkywaters.
I need to revise my above post...I thought back to the last time I changed my font and realized that even the adb method doesn't hold past a reboot now. But I can still use it to install and change my fonts. I like to reboot my phone once a week to keep it clean so I will just add this extra step to my routine to be sure I can continue to change my font should I want to on a whim.