Hylian Freddy | OoT3D Easy setup to freeze timers @HylianFreddy | Uploaded 4 years ago | Updated 3 hours ago
In this video I show a trivial way to get a stopped trade timer that doesn't involve any precisely timed inputs at all.

Basically, if you go to that corner near the gate, sidehop right and keep holding L, the gerudo guard will be unloaded because she's off camera, so you won't get caught even though you're inside the guard's vision range. When the timer expires, the game will stop reading your inputs and the L-targeting will be canceled: this will make the camera pan out enough that the guard will be active again and Link will be caught.
This method does not work if you're at critical health, because the critical camera is zoomed in so much that the guard will stay unloaded even if target is released.
Also, if you want to do this in vanilla OoT, you'll need to add a backflip before the sidehop; everything else stays the same

There's another way to freeze timers without gerudo guards, which is done by voiding out as the timer expires, but I think it only works in the japanese version (likely being the only version exclusive trick in the game). I'd like to be proven wrong though, so if you manage to do it in other languages, please tell me.