Is this funding coming from an EU level mandate and trickling down to nations and then national research programs or is it treating the leaves of the research tree as part of "EU Research" as a whole? I'm not familiar enough the political mechanics of EU research so forgive me if my analogy does not hold.
The EU-as-an-instituion has a budget of 1% of the member states’ GDPs: 1% of ~15 Tr/y, or 150 Bn/y.
Given that, 100 Bn/5 years sounds implausible for a single project for the EU-as-an-institution, so I’d assume it would be EU-as-a-region with the EU-as-an-institution as one of the project partners.