It is definitely an interesting problem, because Portugal is a small enough country that the actual total corpus of available texts in (non-Brazilian) Portuguese is potentially problematic.
Wouldnt it be easier to fine tune a model to convert the Brazilian Portuguese corpus into European Portuguese and then use that corpus?
What a waste of time and money.
Trying to force a LLM into a specific language makes you missed out on most of the world knowledge.
Domain specific models will never be a thing. You don't get generalised intelligence with that.
https://simianwords.bearblog.dev/why-domain-specific-llms-wo...
I'm not sure the direction should be to finetune a small local model for each country or language. These models are already not particularly great at information retrieval, so I doubt anyone would use them for questions like the author suggests (ie who was the president between X and Y). Similarly, they are a little too lightweight to be used for translations too.
If the budget is indeed so modest (5.5 million euros!), I would focus completely on preparing datasets and making sure all open cultural artifacts that we can find are well documented in them. That way every model, private or open, that gets trained in the future could better represent the culture and language of your country.