Pads that are not set to repeat will always start playing as soon as you press the pad's button.
If a style is already playing, pads set to repeat will wait until the start of the next bar before starting and syncing with the style.
On Genos, if you set a non repeating pad to sync start, it will play as soon as you play a note in the 'style' section of the keyboard, whether a style is playing or not. This seems to be the case whatever chord fingering mode is currently set.
This applies to preset and third party pads.
Regards
Ian