HDX will be listed on exchange sometime in Q4, our team is working on it now. The trading pairs show up after IEO at around that time.
And will there be a voting system for coins/tokens lists in hydax exchangers and IEO or launchpad like other exchangers who implement that system? or is it only the team's desire to choose which is more suitable to list on the hydax exchanger?
It depends on the rules made by the team to choose a good exchange to develop the tokens they have later. Like we need to wait for clear information on the team.