I had lunch with a friend who's on the other team. It's been a long time since we've done that. A friend who's on the other team and I had lunch. It's been a long time since I've seen him. Me and my friend on the other team had lunch and it has been a long time....

i really don't know what you want to express by this sentence. But there're mistakes clearly "HAVE LUNCH" not "have a lunch" we can't say like this and in a team, we said "take part in a team" 我不知道你想说什么，但是，很清楚的可以看到，吃饭是"have dinner,have lunch"这是固定搭配; 还有, in other team忘记借此搭配的时候，可以想下熟悉的短语，比如take part in...所以，这里用in If you want to express yourself clearly. You should mainly write down what you want say first step. within subject, predicate and objuct only. Then make it oofy by use other parts. 如果你想表达什么，用最简单的话先写出来（只用主语，谓语，宾语）然后再去用其他部分（定于或者从句之类的）把它表达清楚