Here are a few options, depending on your focus:
- The Impact of Climate Disinformation on European Societies (Most formal/academic)
- The Deleterious Effects of Climate Disinformation Across Europe (Sophisticated/analytical)
- Assessing the Consequences of Climate Disinformation in Europe (Objective/report-style)
Recommendation: “The Impact of Climate Disinformation on European Societies” is the most standard and professional choice for a formal document or article.