>>41520120She has some fire pokemon to help heat up larger material, but welding is done via electrical currents, which is why Wattson's only contribution is a battery. A fire pokemon would just blast the metal apart, it would be more akin to tig welding than the heartier Stick she wants when on the field.
And yeah I tend to like thinking more of infrastructure and background organizations/systems that don't get a lot of limelight in these kinda worlds. Not everyone can run around catching pokemon and having battles for fun after all!