Hello!
Im owner of Lenovo Legion Y520-IKBN laptop
Default settings, that game recommended to me was to disable vsync and enable triple buffering + limit fps to 100. It was working perfectly fine in Legion locations, hovewer, i started to notice screen tearing in BfA starting zone.
When i tried to enable Vsync i was met with horrible input lag, character felt really heavy.
Was trying to enable/disable different options, but what finally fixed that for me is changing DirextX version to DirectX11(Legacy). Somehow now Vsync works as it should and is not going along with input lag (maybe it is here, but almost impossible to feel it).
I have the same laptop, and i’m using directx 12, vsync on, triple buffering on, fps capped at 60, everything at high/ultra, only ssao and shadows disabled/low and i have stable 60 fps. Did you enable vsync and triple buffering in your graphic card control panel?