Now reading between the lines, the horse is going home to your place. Within reason whatever that journey means for a few hours - at the end of the line the horse will be better off.
As for the horse disliking the guy who does the driving - well that is taking things a bit far. The horse will be OK.
But the question does arise as to why you don't like the guy.
Sedation - no I would not do it. Neither would some others who know more about "trailering" than I do. The horse needs her wits about her on a long journey. Anyway - if the trailer has a window at the front then she can enjoy the view.
Come on, get your wits together. It will be OK. Thousands of horse trailering journies go well and the horse arrives the other end, happy to be home.
Fit some boots. Make sure the head collar fits and is comfortable.
WHat the horse does need is for you to lead it into the box - to tie it up, give it a hay net and say - with perfect confidence:
"I'll see you later on" -give the horse a stroke then close the door and get in the passenger seat.
The horse draws confidence from you - if it needs it. So be confident,
When the horse reaches the other end. Let her stretch her legs. Look around. Then take her into her new stable.
Give her a groom . Check she is not sweaty. Rub her back. Give her a treat. Give her a light meal and say
"Good night - see you in the morning."
You might want to sneak in a little later on to make sure she is settling down. Use the excuse of checking her water.
And stop worrying. The antecedents of that arabian of yours
Used to travel around the edge of the Sahara desert - on four feet.
Enjoy your new arrangements.
Barry G