Where to place the fontfile for the FFmpeg drawtext-Filter?

Question

I'm using the precompiled FFmpeg-Android by Bravobit (via gradle: implementation 'nl.bravobit:android-ffmpeg:1.1.5'; based on WritingMind's) with the intention of drawing the current timestamp/location onto a .mp4 file. I am completely new to FFmpeg and have started with Android Studio a few months ago.

Information:

• IDE: Android Studio
• OS: OSX 10.13.5

My problem:

I don't know whether the fontfile needs to be in the Application path on my Phone, in the Android Studio directory or just on a location on my MacBook (so it gets compiled when running the application).

Basic FFmpeg commands (-version, ...) are working, but I can't seem to figure out where I have to place my fontfile.

My current command is as follows:

-i /path/to/video.mp4 -vf drawtext=fontfile=/users/shared/fonts/arial.ttf:text='Hello World' /path/to/output.mp4

I've tried a lot of variations and always received to following errors:

Fontconfig error: Cannot load default config file [Parsed_drawtext_0 @ 0xecbfd420] impossible to init fontconfig [AVFilterGraph @ 0xec9cc140] Error initializing filter 'drawtext' with args 'fontfile=/users/shared/fonts/arial.ttf:text=Hello World' Error reinitializing filters! Failed to inject frame into filter network: Unknown error occurred Error while processing the decoded data for stream #0:0 Conversion failed!

Does anyone have a suggestion on how to get this to work?