Argthtjtr

Anyone got anything witty to say as if I was sort of saying I’m a bit slow in a witty way or a self respectful way but with a bit a humour, sort of like in a melancholic self depreciating way and fashion, thanks

I stumbled upon this lovely catalog : https://dan.hersam.com/lists/not_bright.html

Not all of these are equally respectful, here's a sample of what I feel come off as both witty and appropriate:

A few watts short of a light bulb

Not the quickest bunny in the forest

A few needles short of a sewing kit

Running on 3 cylinders

I discussed a few ideas in the comments above, some of which would only make sense to people of an certain age or locality, however I feel you need to find a well known analogy that is natural to your mind set and tongue.

I would suggest a well known contrasting concept for example the "Hare and the Tortoise" In this case we could say

"Just a minute, I may not be the fastest tortoise off the block but
I'm sure I'll -- finish this / get to the line / be true /whatever"

Whatever you choose has to be natural to your experience, thoughts and everyday language, otherwise you may trip up saying it and potentially feel foolish.

Perhaps you can hint that you are not very alert at that moment by claiming that you are in a fog.

Sorry, but I am in a fog at the moment, so I'd appreciate if you can
repeat that.

TFD(idioms):

in a fog

Not fully aware or alert; having one's attention clouded with
something.

I always feel like I'm in a fog when I take that medication. It's like
it's hard for me to think.

Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

How about ‘sorry, I’m running on an earlier version of software, and I need a moment to process what you’re saying’.

I do also love to say, ironically, in situations where things are going a bit slow ‘turn the handle faster, Igor - the creature is reviving!’ Which is from some old black and white Frankenstein movie, where the assistant, Igor is being called upon to turn the crank more quickly (in order to apply the electricity to Frankenstein’s monster) - so that the monster... will wake up.