A toggle having colour indicates that it is switched "on" - in this case, that means YES. You shouldn't need any further information.
The tick/cross icons can add a fun little bit of flavour to the toggles, but I believe that explanations for toggles generally aren't necessary - the Material guidelines for switches agrees with that idea.
The examples the "off" switches do not have enough contrast against the background. They look to me as if the option was not only "off" but "disabled" as well.
And I would go with the plain switch or the v/x option.
I find Jonny S answer to be the best solution for this question. The reason I would choose the color toggle option is because this will clearly indicate that the option selected is turned on, and when you switch back it turns grey for off.
Hope these answers helps you with your UX processes.