This joint plenary session will highlight the transformative contributions of FAIR-IMPACT and FAIRCORE4EOSC projects to advancing FAIR principles in the domain of semantics: metadata & ontologies, mappings, and research software. The session will open with a keynote from a distinguished expert reporting on the current status and challenge related to the topic within EOSC. The core of the session will feature presentations on key achievement related to theme of the session from the two projects, including guidelines for Research Software Metadata, recommendations for FAIR Semantic Artefacts and FAIR mappings as well as development and setting up of concrete services such as the MSCR and the DTR from FAIRCORE4EOSC and multiple semantic artefacts catalogues from FAIR-IMPACT. The session will conclude with a forward-looking panel discussion, exploring lessons learned, assessing the alignment of outcomes with EOSC objectives, and identifying priorities for future research. This plenary session offers a unique opportunity to reflect on achievements, evaluate the impact, and collaboratively envision the future of FAIR-compliant and semantically enabled science within EOSC.