In the Fuzzy Front End of Eco-innovation, one of the main challenges of eco-ideation is the generation of ideas with a high level of environmental and socio-economical ambition. Current eco-design methods are not adapted to all the requirements of eco-innovation, because of 1) their complexity of implementation, 2) their low robustness and/or 3) their tendency to provide mostly techno-centred solutions. There is a need to define methods which can support multidisciplinary design teams to eco-innovate. In previous work, a set of seven didactical and meso Eco-ideation Stimulation Mechanisms (ESM) was developed, exploring systemic dimensions related to sustainability currently under-exploited.. The proposition first relies on the co-development of an intuitive and didactic formatting of an ESM toolbox to support the eco-ideation phase in multidisciplinary groups. Second, we propose a method in three main steps implemented in a four-hour workshop: a screening phase with the seven ESMs followed by an in-depth divergent phase with a single mechanism, and a convergent formalization of eco-innovative concepts. We illustrate the eco-innovation method by a real-world case study of an interior agency of a co-working building emphasizing circular economy principles and quality of life at work. A group of 13 stakeholders and experts (architects, eco-design experts, local authority and user representatives) were divided into three groups, facilitated by two researchers. The paper shows that this eco-ideation toolbox can be implemented in a real-life context of interior design in multidisciplinary groups involving multiple stakeholders. It supported the groups in sharing a common vision of interior design, and generating three original concepts of co-working spaces.