Sorry to hear you didn’t find an answer to your question but note that this is only one of the many articles published on my website.There are many others from buying the right one, to planting and care taking. 

For Belgium, without any other precautions you could plant a Trachycarpus fortunei, a Chamaerops humilis or a Rhapidophyllum hystrix. These species deal well with our climate and normally don’t need any protection during winter. The Rhapidophyllum is a very, very slow grower by the way. However, when you are willing to place some protection there are many more options; like Jubea chinlensis, Butia odorata, Washingtonia robusta,…

I think the most simple would be to go for a Trachycarpus. They deal well with less sunny spots and are very wide spread so easy to find as well.

For buying tips, planting information etc I would suggest having a look at all the articles on my website.
Kind regards
La Palmeraie

What varieties can I plant in Belgium in a eastern facing garden with partial sun? What steps must I take to do this?

I would rather say a « grove ».

Kind regards
La Palmeraie

Thank you so much for this helpful feedback, it was a bad translation I’m afraid.I tried to correct it to something that should be better.

Kind regards
La Palmeraie