In Studio One Pro 7, licensing Splice samples does not cost credits depending on your plan:
Splice x Studio One
Users with the Splice x Studio One plan can license up to 100 samples per day exclusively in Studio One Pro 7 without using credits.
Sounds+
Sounds+ users can license sounds in Studio One Pro 7 using credits only.
If you're on a Sounds+ plan and wish to license sounds in the DAW without credits, please either switch to the Splice x Studio One plan or upgrade to Creator or Creator+: splice.com/plans
Creator & Creator+
Similar to Splice x Studio One, Creator and Creator+ users can license up to 100 samples per day in Studio One Pro 7 without using credits.
All downloads outside of Studio One Pro 7, such as the Splice Desktop App, website, or mobile app, will require credits.