Rivers host high biodiversity and provide key ecosystem services but are increasingly affected by hydrological alterations. Aquatic communities are shaped by hierarchical environmental filters acting from regional to microhabitat scales, with hydraulics representing a pivotal driver at the finest scale. Over recent decades, several studies have assessed taxon-specific hydraulic preferences allowing the inference of rules to mitigate flow alterations that modify in-stream hydraulic conditions. These studies demonstrated that hydraulic conditions filter similar taxa across distinct rivers, supporting the transferability of hydraulic-based models beyond different contexts. However, previous research has mainly focused on individual taxa or traits, typically evaluating average responses among reaches within a restricted geographical context. Here, we tested hydraulic influences at both taxon and community levels, evaluating responses along the entire hydraulic gradient and across environmentally contrasting regions. We compiled a database of 1,430 macroinvertebrate samples from 89 rivers across 15 regions spread in North Africa (Morocco) and Europe and developed quantile regression models relating 16 dominant macroinvertebrate families and 9 community-level metrics to water velocity, depth, and substrate size. Half of the modelled taxa and 66% of the community metrics responded significantly to hydraulic conditions, with velocity emerging as the main microhabitat filter, with stronger effects toward high values. Baetidae, Elmidae, and Simuliidae, together with Ephemeroptera, Plecoptera and Trichoptera proportion (%EPT), Lotic-invertebrate Index for Flow Evaluation (LIFE), and Shannon diversity, exhibited consistent hydraulic preferences across regions. This univariate pattern suggests that these community metrics can be used to assess ecological status at both reach and microhabitat scales across broad geographic and environmental gradients, extending flow-ecology generality and offering robust, transferable tools for river management.