Both PA and GA administered their elections under non-legislative rules, by court and consent decree. I am not sure about WI, NV, or AZ.
The most effective way to fix that is through those state legislatures, not a court challenge. In fact, a court is likely to demand a response from the legislature even if it hears the case.
Trump will have to invoke his EO and the 75,000 + “governed” patriots will have to insurrect. Not seeing a civil legal pathway to remedy the Communist theft of our free election process.