Based on the green/yellow ground (US is normally just green) and no white or grey (US colors) neutral, I am fairly certain you are outside US/Canada.
Wire colors vary by country. In the US, any color except green (ground), white or grey (neutral) is hot of some type (hot, switched hot, traveler, etc.). According to this chart, if you are in UK and red is hot (as you stated) then neutral is likely black. Based on the other colors availableshould be (in this specific diagram for specific countries)black, that leavesand yellow & blue also asare hot wires.
But to know for sure, we need to know the country/region.
It also looks like you have two identical switches, but more description - and/or a picture of the front of the switches - would help.