Quote from: Freedom4All on Today at 01:31:03 AM

I set up a website in 2019 mainly aimed at Dutch speakers.
The website is an independent news and opinion website with loyal followers.

It is definitely necessary to better define your site and the approximate offer you expect

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I never wanted to monetize this website and not participate in GoogleAds and Affiliate programs from the "ordinary world". Principally not.

What is wrong with Google Ads or Affiliate Programs even from the ordinary world? Why do you think it is desirable to avoid it? It is a completely legitimate way to do business.

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I tried AdSense but removed it again

Again, it is unclear why you turn off the ad network, while at the same time you are looking for sponsors. Certainly, AdSense is not the only one, there are other choices.

Quote from: Freedom4All on Today at 01:31:03 AM

Our readers are mainly adults from 30 years old and all ages above.
We have a newsletter with hundreds of subscribed readers. We have a clean chat/comment section. It is moderated to keep trolls away. It's a serious website with multiple writers.

You have to provide more precise statistics, this seems like your guesswork. If you are not going to share the link to the site, you should provide basic information, the daily number of visits to the site and at least some demographic information about the visitors.