I wouldn't send a video unless she agrees to see it.
You said it well, seeing a provider once to build a rapport and see where the next encounter can go is a great idea. Generally, what we offer in a session depends on the chemistry, so that path is a good one to follow.
Otherwise, I like to know before booking if some services are a dealbreaker, it is then better to ask the provider if she offers them to avoid time wastage on both sides. Don't ask what she offers, instead ask for exactly what you want. Some might not be open to answering this kind of question, be aware. If no services are a dealbreaker, then don't mention anything.
The kind of special requests that annoy me are the ones that don't let the session go with the flow at all or try to change the way I look. Personally, if you want to use me as a canvas to have your sexual fun without caring about who I am, what I say and sharing something with me, it's a session I will hate and that you will dislike as well. We know when you wrote to us because you liked our profile, when you are interested in seeing us, in knowing what we can offer and bring to the session and see what we can share together, and this is what going with the flow means. So one request is a thing, but controlling my looks and/or what will happen in the session as if I am a metronome is not the kind of encounter that I appreciate and will refuse to meet you.
In other words, it's important that you contact a provider that represents what you are looking for and can or wants to accommodate you instead of asking another provider to change to fit your fantasy.