Sustainability reporting has become a crucial tool for global corporations to disclose environmental, social, and governance (ESG) aspects. This paper examines how corporate sustainability reporting depth varies with firm financial characteristics and with the institutional diversity of European economic systems. Companies are classified using the Varieties of Capitalism (VoC) framework, accounting for the economic differences represented by distinct capitalism models. The quantitative design applies dictionary-based text mining to 2022 and 2023 sustainability reports, using ESRS-aligned scoring to measure disclosure breadth and topic coverage. The sample includes the 20 highest-revenue firms from each VoC group. WordStat-based text analytics generate ESRS topic scores and link disclosure outcomes to firm size, profitability, and leverage. Results indicate systematic cross-VoC differences in ESRS coverage, with higher median disclosure breadth in Social-Democrat Economies (SDE) and Mediterranean Capitalism (MED) settings, thinner coverage more common in Continental European Capitalism (CEC) and Eastern and Central European Capitalism (EAST) settings, and Liberal Market Economies (LME) typically occupying an intermediate position. Regression evidence identifies firm size as the most consistent positive determinant of disclosure breadth, while profitability shows weaker or inconsistent associations and leverage is more often linked to thinner environmental coverage. Findings imply that achieving ESRS comparability across Europe require not only harmonized standards but also institution-sensitive implementation and enforcement capable of reducing persistent cross-country differences in disclosure depth.