I'm in the middle of repairing a crack in my 30+year foundation wall using QUIKRETE Hydraulic Water-Stop Cement. It's been repaired before, I've been in the house for over 10 years, previous owner must of done the repair. As you can see from the photos it's a big crack, I chiseled it so that it has inverted V shape, recommended by manufacture. There is no way that I can repair this all in one shot, recommended by manufacture. They say that it might leak from the two or more joints of Hydraulic Water-Stop Cement. Has one did a repair with this QUIKRETE Hydraulic Water-Stop Cement and had to mix 2 or more batches to finish the repair?
If you already have purchased the product, you will have no choice but to work fast. You will definitely need to make more than one batch. Just get the new batch made as soon as you can, using more than one bucket if you need to save time from having to clean the mess of the first bucket.
I seen the method they prefer for small cracks, applying it by hand. I would suggest trying a masons slick
They come in various widths, from 1/4" to 3/4" and possibly wider. I would try a 1/2" to get the cement in the bottom of the cut and fill it up about halfway with the first mix and top it off with the next mixes. This tool may take some getting used to and you may be better off cramming it in by hand. But this is what I would at least try.