Team setup, help needed

I got these pokemon I want to use which 6 are best : milotic ,Espeon ,porygon z, blissey ,scizor, salamence, blaziken, weavile, gallade, archeops, zoroark, hydrogien ,volcanra, dragonnite, tryantir,excadrill ,garchop, metagross, gigalith, lucario.

I would say
Scizor, Hydregoin, Volcanra, Metagross, Lucario, and Milotic. But any six would be a good six.

Ok I will try that

Ok good luck. :)

what are there speed and moves

It really doesn't matter which pokémon; it matters which moves. I.e., If the Lucario only knows fighting type moves avoid it completely. Make it tricky, like a fire type is good against lucario, so teach it a water or ground type attack so surprise somebody trying to defeat it with a fire-type. My team is completely unexpected like that

I'm pretty sure he/she got his team done