To join vVAQ, you should own a HOTAS, microphone, and the DCS F/A-18C module with basic to intermediate understanding of the aircraft and its systems. A full list of the prerequisites can be found here.
Training is done based on pilot availability, however most flights are done on Friday, Saturday, or Sunday evenings in US timezones.
The EA-18G is simulated with the CJS Super Hornet Community Mod which changes the external model, sounds, cockpit, and stores of the DCS F/A-18C module but does not overwrite or change the DCS F/A-18C module.
Electronic warfare unfortunately can't be simulated well in DCS. We use a combination of scripting and trigger zones to emulate EW to the best of our abilities.
We use the Caucasus Map to emulate the airfields, training facilities, airspaces, and routes of Washington State and NAS Whidbey Island where the majority of the US Navy's EA-18G fleet is based. Other maps that would be good to have are the Nevada Test and Training Map and the Marianas Map.
Yes, all pilots need to graduate from the VAQ-129 syllabus which includes aircraft familiarization, SEAD and EW, and limited BFM and BVR sorties. However, you need to have a basic to intermediate understanding of the DCS F/A-18C module prior to starting the course. The syllabus should take about 6-10 total flights.