If you find it too spicy, leave it to mellow for a day in the fridge. The flavours will blend a bit more and it may seem less spicy then.  If it is still too spicy, you could add some vegan yoghurt which will pull down the heat and soften the flavours.  It is always easier to add more chilli than to take it away so, when you make zhoug, start with less chilli and then add more if you think it needs it.