So basically how the creation process for certain types of bots is different so here is an list of the cybertronians that can't be created so easily and an quick explanation what I mean is the main character has the ability to create basic Cybertronians like workers and soldiers but he has to create certain items to create certain cybertronian units for example the recipe for creating an combiner.
Combiner recipe:1x C-E,onyxium atomic core
Titan recipe:1x Z energon,hypertanium core.
Prime recipe:W-energon,fused alloy core.