Introduction: The nursing team is crucial in emergency care (EC) settings, serving as patients’ first point of contact. However, gaps in their training have been hindering the effectiveness of care and patient survival. In situ simulation (ISS) has been recognized as a valuable tool in EC education, uncovering hidden risks in clinical care areas. This study aimed to analyse how an ISS educational intervention in the EC department impacted participants’ clinical and transferable skills. Methods: To assess the effectiveness of an educational intervention on the 37 EC nursing professionals, a 12-month study quasi-experimental study was conducted. The study consisted of a survey to identify participants’ learning needs and four workshops tailored to meet the team’s specific needs, culminating in an ISS session. Knowledge levels were evaluated using pre- and post-tests administered before (T0) and after (T1) the workshops, along with a formative assessment with an Objective Structured Clinical Examination (OSCE) holistic marking guide to measure the clinical and transferable skills acquired during the ISS. Results: The primary participant’s learning needs centred around cardiopulmonary arrest caused by acute myocardial infarction, including interpreting electrocardiogram and teamwork. These topics were used to develop the workshop and the simulation scenario. A significant difference (p < 0.001) was observed in the levels of learning between T0 and T1, indicating a marked improvement in the participants’ performance. The nursing professionals displayed proficient clinical and transferable skills during the ISS, successfully completing over 80% of the OSCE items. Discussion: These findings suggested that a customized educational intervention incorporating participatory learning and ISS effectively enhances clinical and transferable skills among nursing professionals. The positive outcomes observed in post-tests and OSCE holistic assessment highlighted the effectiveness of this intervention for the EC nursing team. The results of this study demonstrate that active participation in workshops facilitates knowledge acquisition. Furthermore, the OSCE results illustrate the practical application of clinical and transferable skills during the ISS.