Each Agile team creates its own culture. Moving between teams, and specifically Agile teams, is not only about different work or different team members to work with; it's mainly about adapting to different team cultures.
Team culture takes time to evolve and — like any other type of culture — it will resist a change, no matter how small it is. That change can be in the form of new person (like you), or it can be in the form of new idea that you want to implement.
Remember one thing: Your new team is going to resist you, even if they don't say so openly! So how do you adapt to a different team culture?
I've worked with five different teams in less than a year, and, every time, culture shock has hit hard at the beginning. But once you're used to it, it will become a learning experience. Once I learned that the tendency to resist was natural, there were no hard feelings and no personality clashes.
Different Agile teams can take different approaches to a task. As I experienced in one team (I'll call it Team A), QA guys started testing the stories when the developer said, "Story A is ready for testing" in the Daily Scrum. The QA guys in Team B, however, only started to test when a developer or PM sent a specific email to the team stating, "Story A is ready for testing." This was true even if Story A's readiness was already mentioned in the stand-up meeting. Initially, as a new member of the team, I insisted on not sending a "ready for testing" email. But then I realized that since Team B is geographically divided, sometimes they would miss a few words during the Daily Scrum, and that was why Team B QA members relied on such an email.
In another incident, I observed that QA and UAT (user acceptance testing) members of Team B met daily to be in sync, which was totally different from what they did in Team A. There, QA and UAT folks simply relied on the Daily Scrum. Initially, I wasn't prepared to handle these "extra" daily meetings with Team B; I thought they were a waste and should be stopped. When I tried to make this change, the team resisted, as expected. I realized — after some time — that if these daily meetings were helping the team, then there was no harm in them. I started to facilitate the meetings instead.
The best way to adapt to a new team culture, I've found, is to watch and wait. As a new team member, it's better not to force new ideas on the team but, rather, to observe and learn the methodologies and culture team is already working with. Once the team starts accepting you, you can slowly and gradually introduce your own ideas. Initially, you might perceive personality clashes or even an ego clash, but it's usually just a different team culture that you need to — and can — learn. So don't rush to conclusions, and don't try to judge a team based on its working methodologies. It's not the team but you who works differently, and it's you who needs to adapt to the team culture.
People spend time and money to travel to different parts of their society or of the world, just to know more about different cultures. So if you get the chance to learn a different culture at work, consider yourself lucky!