Yes, there are ESA sponsored accounts available. Go to OSEO page and choose a "Submit a Proposal for the OGC EO Interface Integration Service" option.
Make sure you include most relevant information:
- which services you need (e.g. Sentinel Hub, Batch Processing, etc.)
- in case access to commercial data is needed (PlanetScope, Airbus Pleiades or Airbus SPOT), state the desired volume
- the planned volume of data uptake, best to reference to processing units or sq. km
- desired duration of the access (up to 12 months)
- scientifically relevant results planned to come out of the exercise
- in case of business exploration activities some plans for long-term sustainability