FYI -> Unreal Engine 5.7.3 uses python 3.12 for their internal python scripting tools.

[Kaen-SG]

Unreal Engine 5.7.3 & Python

With the release of UE 5.7, Epic updated the internal environment. Unreal Engine 5.7.3 uses Python 3.12.x as its internal scripting base.

This confirms why your earlier build failed: you were attempting to use Python 3.14, which is still ahead of the engine's current integration and lacks the necessary pre-built binaries.

So for better compatibility... use Python 3.12.x
It might explain some of the problems I've been having.