A work around for some with intermittent crashes has been to use dxvk. This will redirect directx calls to vulkan. This may not work for everyone, but has shown success with a number of people.
You unzip the DLL files into
Code:
FINAL FANTASY XIV - A Realm Reborn\game
folder. If you want to stop using vulkan, just delete the DLL files.
DXVK can be found here:
https://github.com/doitsujin/dxvk/releases/
This is not compatible with reshade as they both work by placing DirectX DLLs in the game folder. It may work if Reshade set to vulkan, but I havn't tried it.