Looking at it I found that the ScanAll method in Region X.m is what you need. Region X is more interesting because although it doesn't directly serve your purpose, its source is available. DVD Info X will display the region code of your drive without requiring to have a DVD inserted.

Intel® Core™ 2 Duo E6750 (2.66MHz), AMD® Phenom 9450 (2.I found some utilities that are capable of dealing with DVD region settings on OS X: DVD Info X, and Region X. Windows7™, Windows8™, Windows8.1™, Windows10™, Mac OS X 10.11, macOS Sierra 10.12, macOS High Sierra 10.13, macOS Mojave 10.14 Minimum System Requirements - Write/Read BD/DVD/CD Minimum System Requirements - 4K Ultra HD Blu-Ray With BDXL and M-DISC support, you can now back up your files with fewer discs than ever before, and since the drive is portable and USB bus powered, all of this can be done virtually anywhere. Power2Go® 8 gives you the ability to burn your valuable files to Blu-ray (including triple and quad layer BDXL discs), DVD or CD media. PowerDirector® 15 LE allows you to import your home movies, edit them, and then upload them to social media sites. PowerDVD™14 delivers award winning playback software and will even upscale standard-definition content to high-definition quality. ( ) Product key for free download is included. It is needed to be downloaded through the WEB. The BDR-XD07TB includes CyberLink Software, “CyberLink Media Suite 10” only for Windows OS. The portable device, measuring only 133mm (W) X 133mm (D) X 14.8mm (H) and weighing a mere 230g, also has the ability to be powered directly via USB (no AC adaptor required). The ultra-compact 133×133×14.8mm USB 3.0 drive can read and write to all BDXL discs1 including BD-R triple-layer 100GB media, BD-R quad-layer 128GB media, and BD-RE triple layer 100GB media, as well as conventional Blu-ray discs (single-layer 25GB media and dual-layer 50GB media). The BDR-XD07TB is one of the world’s smallest and lightest BD/DVD/CD portable burners supporting BDXL and M-DISC.

Mac dvd drive region alert