This is kind of loaded question, simply because there are a TON of criteria you could use. Are we talking JUST cartoons, or entire product lines?
Personally, all things considered, I think Hasbro probably invested the LEAST in Robots in Disguise 2001. The show was already financed by Takara, who had also already tooled and produced the toys. I’m not sure how much Hasbro put to Saban to get them to license and dub the cartoon, but I assume it couldn’t have been much since Saban ended up retaining rights for the series. Toy investment was minimal, with some minor retooling and the only new molds being a quartet of sub-basic level figures (And salvaging some leftovers from Beast Machines).
I think, for Hasbro, RiD01 ended up being the cheapest franchise entry to produce and had probably some of the better returns (excluding movie pushes).