Try using EEVEE with viewport samples set to 1. Workbench has (non working?) Antialiasing option (under Film wtf?) but seems to only disable AA while transforming the view (even if AA is enabled).
AA seems a hot topic, as for some things it’s nice, but not at all for others, and controls are all over the place and with different effects (and bugs?). For example Blender 2.8 Wireframes Discussion