If you incorporate your company there, you can get instant residency via the “Professional Card”.
Once you are a legal resident there, they don't count the days you're there, so you don't need to be there full-time. You should plan to hire at least one local Belgian employee.
Then, after 5 years of residency, assuming you've learned conversational French or Dutch, depending on where in the country you reside, you're very eligible for Belgian citizenship.
Email me if you want details or a referral.