There is no stutter. Rather there can be a pause trying to do a fast start after taking your foot of the brake until the motor engages (nothing to do with the DCT which is already in gear). Seems to be by design engineering wise and software controlled. Early models received a firmware update that alleviated this issue but did not eliminate it. I haven't experimented myself with this, but Sport mode sharpens the responsiveness, and may help reduce any pause. Another thing one could try is launch control, left foot on brake and right foot on accelerator.
I seldom care about a fast start and the only time it really applies (for me) is crossing a road with traffic at a stop sign, or turning with traffic from a stop. I've just adjusted to this quirk and floor the accelerator half a second before I would in other cars. No issues in motion. My major issue with this lag in electric motor "crawl" is adjusting an inch or two in my garage. That's jerky and imprecise! You cannot simply lighten up on the brake pedal like ordinary automatics to move a smidge because of the pause in crawl function.
2018 Kia LX HEV Metal Stream with Advanced Tech