Getting Started

I primarily prefer to print with PETG for functional prints, and I am finally starting to get pretty reliable tool changes and tip shaping for PETG. I, however, would love to be able to use PLA as the support interface extruder to allow easy support removal, however, I am having trouble with tip shaping for the 2 different materials since they need different temperatures and behave differently. My question is if there is a way to have different toolchange g-codes for different material, whether its some sort of conditional statement or using formulas that base the toolchange off of the print temp, instead of an absolute temperature value in the gcode? Maybe this is too difficult to do with tip-shaping and a 3D Clippy is the only real solution, at which point I could use some direction on setting that up for my Elegoo Neptune 4 Max, and where to find the bill of materials/ STLs for making a clippy. Also my recent attempt at a multi-material support print in Fluidd/Klipper resulted an an error "Invalid speed in 'G1 F-2147483648" and my understanding is this is a bug in a macro relating to CP Toolchange. It seemed to occur during the second toolchange back to PETG and not the first one to PLA. If anyone has any tips or guidance relating to any of this, any information would be much appreciated. Thanks a ton in advance!