As a Portuguese why would there be a significant Portuguese representation in fighting games? Or most games for that matter, the reason why Portugal is pretty significant in football games is because Portugal is pretty good at football (we spend so much money on it), now if we were talking about historical games within certain periods, yeah sure then it makes sense to have Portugal there, and there have certainly been games that did a really poor job at it, but most games aren't set during the Age of Discovery (Early Age of Discovery even less so).
Are there good stories to be told involving Portugal that aren't even about the age of discovery? Yes, there are, but developers from other countries shouldn't really be the ones that have to go out of their way to tackle them, because most countries especially those that have been around for a while now also have great stories to be told, realistically the people that should be telling these stories should be Portuguese studios, which there are ofc very few.