Sorry for the delay--laptop broke.

Cues, I mostly just exactly memorize the music and practice individually with the conductor if needed. I've also had whoever is sitting next to me nonverbally let me know, by poking me or something, also have done that with standing at the end of a concert. Conductors can be jerks but some are flexible.

Cues are something that I generally hit much more often in musical theatre and honestly, it's something you solve as it comes up. You often have to have some interaction with the musical director (in theatre) or the conductor or session leader or whoever it is, which is not ideal. It was actually someone from the classicalmusicians subreddit who said to me that you should basically have the goal of never being spoken to the whole session! But unfortunately that's not always realistic if you need a cue.

I'll talk about theatre because that's what I know best but I expect you would find something similar in classical. I find it breaks down into basically three categories. If it's not a cold open, or at least not for you, then you're fine. It may mean hanging around in a state of being ready to go at a heartbeat's notice for a while, but you can just be aware when everyone else is playing and go with it. If it is a cold open and it's just you and then everyone else joins, again, you're fine within the limits that it lets you set the tempo and they have to be OK with that. It doesn't happen very often for me as a bassist but it depends on what you're playing. The tricky situation is if it's cold and you are required to come in with everyone else. In theatre the musical director will often count it, or in both theatre and classical recording sessions there may sometimes be a click or recorded track to play to. Even if there's click it may be that you need counting in because you won't know which is the down beat, but if you're in an open concert sort of situation there may not be anything but the conductor, and that's where you have to get creative.

You will need a good relationship with whoever's in charge but I've done all kinds of things. I've put microphones on people so they can count really quietly under their breath and not ruin the recording (I own a radio microphone and a tiny mixer so I can mix it into my own monitoring). I've clipped that microphone to someone's cuff so I can hear their arms waving around which works amazingly well depending on their conducting style. I've given that microphone to other people so they can act as interpreter. Sometimes that's another player or a session leader or something, or just one of the engineers. I very rarely have to do any of that, though. At a big studio they will probably be happy to sort something out for you. You figure it out.

On one hand they are required to make reasonable adjustments. On the other hand you are asking for special favours and you don't want to be the perpetual special case. Make sure you flag it up early so it's not a surprise and take a problem solving attitude. I go to every job worrying that I'll be confronted with something I can't solve, but so far, so good.

And yes, I can't take jobs that require sight reading. That's really simple. But it's not my impression that most jobs do require that. I often get sent music that I have to have a friend go through on piano so I can learn it, and I end up owing her a lot of lunches. It's not something I want to do, but if it's that or unemployment I'll put up with it.