OpenGL is a bit like Vulkan, but discontinued since… 2014, with a single update since then. It was actually stopped because Vulkan seemed better, and both API’s were maintained by the same organisation.
In general it’s more likely to work on older devices, but would be less performant than Vulkan.
FemShep was in game sculpted until the third game, which is why it looks weird and changes so much from game to game. BroShep on the other hand was a 3d scan of Mark Vanderloo I believe.