There are two reasons to prefer 0W30 over 5W30. Firstly, its resistance to flow (cold viscocity) is lower, so will be beneficial if you live in a country where you are driving in temperatures below freezing for a significant part of the year. Secondly, for the same reason, it reduces friction marginally during cold starts and for a very short time whilst the engine is warming up, which marginally reduces emissions. Outside of those two criteria, as both oils have the same warm viscocity, they will perform alike, all other conditions being equal. Vehicle manufacturers have been increasingly specifying oils with the lowest winter viscocity they can get away with over recent years, in the quest to reduce emissions even marginally. Every 0.00000001% reduction helps them with their overall emissions rating and reduces the costs that they have to pay governments connected to their overall vehicle range emissions ratings. Hence stop/start technology and intelligent alternator charging systems, DPF filters, etc., which are not necessarily beneficial to the performance and life of your car, complicate its operation and reliability, but reduce its emissions.
In moderate or warm climates, 0W30 has no benefit over 5W30, and in hot conditions may actually be harmful to engine life. Hence for several years, and still in some regions, Volvo North America mandate 5W30 oil in all VEA engine Volvos, rather than the 0W20 oil that is stipulated in Europe for VEA engines.
Bottom line: use the oil that meets or exceeds the Volvo specification for your engine and model year. As long as it has been produced to meet that Volvo specification, its grade and ACEA rating will follow and also meet the necessary requirement. So look for the correct Volvo specification on the label or in the technical data sheet.
