If your company requires interview to transfer _internally_, you should consider leaving. Microsoft was like that (maybe still is, I don't know), and it was easier to get a job elsewhere than to go to a desirable team.
Microsoft definitely still did as of late 2017, when I was still there. You're absolutely right, it was easier to just get a job elsewhere and that was what I did! Hah. I'm trying to avoid that here, because I like the company, just hoping to work on a different product.
Is a transfer interview not common elsewhere? Anyone know if Amazon or Google requires something like that?