According to the eco-social education paradigm, landscape plays a key role as an identity object of study in the interaction between nature and society. The study seeks to assess a practical experience conducted among trainee teachers consisting in the systematized analysis of local and foreign degraded landscapes in Spain and Colombia, based on environmental, sustainability and global-citizenship literacies--guarantors of eco-social education. A mirror class methodology was implemented among 127 Spanish and Colombian trainee teachers. It comprised an online videocall exchange between different teaching groups. A quasi-experimental research methodology was followed, based on the didactic and statistical analysis of the trainee teachers' reports and a validated questionnaire. The findings reveal a global didactic acquisition of 2.9 points on a 4-scale evaluation range. The learning was higher in didactic tasks related to the landscape analysis and lower in comparative local-global analysis tasks. A statistically significant learning development of +0.8 points was found. The results suggest that the study of local landscapes captures interest and mirror classes easily bring distant realities closer, thus improving the eco-social knowledge and the feeling of an eco-social responsibility for global sustainability. Moreover, the experience in trainee teachers assures a didactic transfer to the wider population.