Its an active research area, there are proposals like helios https://en.m.wikipedia.org/wiki/Helios_Voting which check some of the boxes but aren't perfect . I'm sure cryptographers would love to come up with a fully scalable, trustless, verifiable, anonomous, coercion resistant system. But that's a hard set of properties to satisfy especially if nothing is in the physical world.

If you allow physical voting places, then just make a machine that gives a paper recipt and do risk limiting audits. Problem solved.