Breakfast 90 min before half-marathon?

Why not? You either care or you don't. Your unwillingness to wake up early indicates you don't.

As to what to eat and when, that's so highly individual that there's no way anyone can give you meaningful advice. What do you normally eat before running? Do that. What works for someone else may or may not work for you. I have a friend that swears by pop-tarts as a pre-race meal. No way I could do that - those things jack up my stomach. Do what works for you, and only you can find out what that is.

I’m not as fast as you, but for a half marathon I’d eat a small piece of toast with butter 1.5-2 hours before, take a gel at the start, and take another gel 45 mins in. Taking calories doesn’t make you weak — whatever works!

So it “feels stupid” to take a gel? It depends on what you want from the TT. You can look at studies regarding carb intake and perceived exertion. I don’t know how conclusive they are, nor how much this might affect you.

Maybe you’re fine with getting a read on your fitness without going anywhere near all-out. Or maybe it’s an opportunity to experiment with things like how you respond to waking early, to taking a gel, etc.

Why don't you try something in practice?

When I do a long race (marathon or HM) or important time trial, I wake up 3 hours before start time so I can eat, drink coffee and have my PRP (pre-race poop). That can mean getting up crazy early, which I don't like to do often. But there's nothing worse than getting the urge to take a dump during an important race or time trial.

For regular daily runs, which is 99.9% of the time, I don't bother with any of that. I just wake up, have a little water and head out the door.

Everyone is different. I would get sick to my stomach if I tried to run within a couple of hours after eating anything significant. I never ate anything before a half-marathon. I tried eating very small amounts before marathons but it didn't seem necessary--I did just fine on an empty stomach. I realize I may be unusual, and you need to find out what works for you.

1/2 bagel and peanut butter with coffee 2 hrs before. Was never able to stomach a gel in anything shorter than a marathon.

3 or 4 days before a desired 'timed run' is not the time to be asking this type of question. Your sleeping, waking, eating (fueling), hydrating and bathroom breaks are something that need ironing out for that particular "you' should be worked out a year or two in advance so as to tweak it all to the unique 'YOU'. Training is not just running - you need to train your body's daily functions.