I just watched her once on one of the videos for a whole game. I don't see any BT in her game.
Mir looks like an "off-the-ball hybrid" offensively. The game didn't show any skills of her ball-handling or shooting other than 5 feet and in (maybe she has it but the game didn't show because they kept her inside the whole game.). BT had handle and could shoot from the outside. Mir jumps out of the gym. BT didn't really have great hops. Not bad but not much. Mir has great, great hops. She doesn't appear to be a scorer but you have to wonder with Paige as the team's pg - if Mir isn't really a scorer she could still "flourish."
Mir is also skinny while BT was more rugged. Mir seems to have very long arms- BT didn't. BT wasn't much if at all of an offensive rebounder. Mir can be due to her hops and arms. She seems to get her hands on the ball a lot inside even if she can't pull down the rebound. I don't think she is "the best rebounder in her class (but "pound for pound probably a BIG yes)" but because of her freak hops and long arms (she is a quick jumper) and she'll be playing in a motion offense - she can create some offensive chaos in the paint though teams with good quickness from their "very big" bigs will probably be able to neutralize that aspect.
Didn't get a chance to see what she could do defensively. They had her pinned in the back of a zone or defending inside. But if she could move well laterally defensively -- she could be a defensive freak on the perimeter but would need help vs "powerful/sturdy" power forwards. Depending on her quickness laterally - she could impact the game much differently than BT did. And she could probably be super in help defense - such as coming from behind/or weak side tipping balls and blocking shots (even blocking much, much, much taller players) But offensively right now I didn't see her try anything that BT was able to do. Not saying she can't. I only saw one full game from her.