The pitch bend control is the left slider, found on the left of the keyboard in the User Interface.
All of the content in Splice INSTRUMENT is curated by the development team. Because of this, some instruments do not respond to pitch bend functionality as their timbre does not play well with pitch bend. This is especially true for the libraries found under the "Spitfire Audio" label in INSTRUMENT.
If you need to bend the pitch of a preset that doesn’t currently have pitch bend enabled, here are some potential workarounds:
Use a frequency shifter as an audio effect and automate it
Export the region as audio and stretch/pitch shift the audio
We are always open to feedback, and if you feel that having pitch bend across the entire instrument is important then please use the "Feedback" button in the plugin, or simply fill out the form here to let us know.