Among news disorders, propagandist news are particularly insidious, because they tend to mix oriented messages with factual reports intended to look like reliable news. To detect propaganda, extant approaches based on Language Models such as BERT are promising but often overfit their training datasets, due to biases in data collection. To enhance classification robustness and improve generalization to new sources, we propose a neurosymbolic approach combining non-contextual text embeddings (fastText) with symbolic conceptual features such as genre, topic, and persuasion techniques. Results show improvements over equivalent text-only methods, and ablation studies as well as explainability analyses confirm the benefits of the added features. Keywords: Information disorder, Fake news, Propaganda, Classification, Topic modeling, Hybrid method, Neurosymbolic model, Ablation, Robustness

Narratives are a new tool to propagate ideas that are sometimes well hidden in press articles. The SemEval-2025 Task 10 focuses on detecting and extracting such narratives in multiple languages. In this paper, we explore the capabilities of encoder-based language models to classify texts according to the narrative they contain. We show that multilingual encoders outperform monolingual models on this dataset, which is challenging due to the small number of samples per class per language. We perform additional experiments to measure the generalization of features in multilingual models to new languages.