A group of members can get together and on their own arrange for the translation of a proceeding or a meeting they might have. But in order to call a subgroup together and ensure that all the services you're used to having at a committee are present in order to transact a proceeding, we need a formal structure such as the steering committee. That's why it comes up in the routine motions at the beginning of each session, explicitly asking the members whether they want a steering committee or not, precisely in order to get together as a smaller group.
Obviously, if members of the committee want to get together informally and arrange for whatever sort of translation you might want—say, in the chair's office or some other location—you're always free to do that, and I can provide whatever assistance I could in that regard to facilitate it. But in order to actually have the subgroup come together to talk about these things, we would probably need a more formalized structure, which would be a formal steering committee.