If you are using macOS 10.14.6+, you can accelerate applications with the external GPU (if they support GPU acceleration)...
Select the app in Finder
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Check Prefer External GPU
Adobe Premiere and Apple Final Cut Pro automatically use the eGPU when appropriate. Do not select Prefer External GPU for these applications.
Some professional applications let you select the external GPU (or multiple GPUs) in their preferences.
The Opticis DPAX DisplayPort 1.2 Data Recovery Repeater is an active repeater for DisplayPort video signals, increasing video transmission of a DisplayPort signal up to a combined length of 18m:
Locate repeater up to 3m (10ft) from the Source and up to 15m (49ft) to the Display at DP1.2.
DPAX complies with DisplayPort 1.2 standards and supports Ultra High Definition (up to 4096x2160) at 60Hz.