Please do not post a support request without first reading and following the advice in https://retropie.org.uk/forum/topic/3/read-this-first
ComicBook Theme Launching Images
Can that be done and if so what do I need to do?
The splash images are not part of Emulationstation, but part of the launcher - Runcommand. So, unless you find a substitute for it, the answer would be no.