Last I heard about this, they did not fully commit on a singular technical solution yet. The closest I know being NGI Taler (FLOSS, created by a Swiss company, and plans a lauch in Euro this year), but it doesn't support offline payments yet, unlike what the digital euro's brochures say.
Hopefully this will be resolved, but I hear this is a very polarized subject since it would remove a lot of powers from the banks (by concentrating it around the ECB), and they are lobying heavily against it, and the right wing is listening.