@bendurso If your brand is new in the market, I recommend selling with both ways (your website and resellers-marketplaces).
Because since there are tons of alternatives in the crowded plugin ocean, reaching to the audience is harder nowadays, even the product is good. Marketplaces have the dedicated audience database and they will help to promote your plugin. Of course there is a price for this service with commissions
Recently, iPhone has restricted receiving some social media ads due to personal data protection laws. Reaching the audience is more difficult now than it was a few years ago. This disrupted the advertising business of resellers. But resellers still help to reach the dedicated user database directly.
You also still need to sell on your website because some users want it. Yes, some users want to buy directly from the manufacturer. I think this is also necessary for the prestige of the brand.