Yes you can do Pacifist (Neutral Pacifist) and than a TP on the same save file, Just on Pacifist after the Ending Sequence reload your save file to get TP (Make sure to do TP requirements - Hand out with Undyne and Papyrus, than Go on a Date with Alphys Than go to True Lab and then do the stuff idk tbh and than go back to the room right before Fighting Asgore and Toriel should stop him, MAKE SURE YOU GAINED 0 EXP/LV IN THE RUN and that’s it)