when an opponent wants to play a card or an effect from remaining resources
can i steal those before they can be spend?

I would say no since the resources are a cost to play a the card and I you can't respond to the payment, only the effect.

You could however take their resources during the kingdom phase, restricting size and number of cards they can put into play during the capital phase.

and as well between the opponents moves

i just stombled over it and wanted clarity about it :)