Based on what I know from English grammar, team should come after the name. The examples are "Soccer Team", "Basketball team", etc.. But recently I've seen some indie developers naming themselves as "Team [name]". Team Meat is an example of that, or Team Snore. And watching a commentary, I've heard them say "Team Na'Vi" or "Team Orange". So I was wondering if such an structure is acceptable or not?
OP's examples aren't really postposed adjectives in the normal sense. As discussed by British linguist David Crystal in his blog entry On Team GB, this "restrictive apposition" construction is essentially the same as...
Mount Everest (= the mountain that is Everest)
Queen Elizabeth (= the Queen who is Elizabeth)
my brother Fred (= my brother who is Fred)
the number six (= the number that is six)
Hurricane Katrina (etc., etc.)
That's to say, Team Meat = the team which is, more specifically, Meat. As Crystal puts it, the superficially "reversed word order ... does have a certain rhetorical punch", making it attractive when you want an "imposing" name for your team/whatever.
Personally, I think there's also an argument for saying that to some extent the prepositioned "noun" (team, in OP's case) actually functions both grammatically and semantically as an adjective. The primary "identifier" of the entity is Meat, which is specifically qualified as being a type of team.
A basketball team is a type of team, i.e. a team that plays basketball.
Team Meat is the name of a team. So, Team Meat is a specific instance of a team. It doesn't tell you what they do.
Team - Shashank is an acceptable structure . It indicates that the team is named as shashank . Soccer team , basketball team are the types of teams and not the name of the team per-se.