OSB board on paving stones in carport

Hello everyone... I am new here and have a question for my new project:

I have attached a carport to my house… completely made of concrete with a terrace above it. The interior floor is paved with concrete pavers (underneath mineral and gravel). Now we want to turn this carport into a small hobby workshop/storage room. For this, we want to glaze the entire front area and insulate the side walls (towards the ground/outdoor area) as well as the ceiling. Now the question for us is what to do with the paved floor, which until now has always been dry and even. Since we are thinking of an OSB board floor, we thought whether we could lay a relatively thick PE foil on top of the pavers, glue it, and run it under the external insulation. On the PE foil then a substructure with insulation in between (height?) and then OSB. Would this be a feasible construction? The floor is level and there have been no settlements so far. Also, no extraordinarily heavy machines or items will be placed inside. I would be grateful for your answers and contributions.

It swells because it is not glued to be moisture-resistant.

yes, but there is a foil underneath so that no moisture can rise???

I would also not use OSB boards, for the same reasons Nordlys mentioned. Should they then remain exposed or do you want to cover them? Honestly, since the walls are concrete, I would tear out the paving, pour concrete, and either seal it or tile it, depending on what work is to be done.

OSB boards would remain overnight....possibly treated with oil. Concrete walls will be insulated from the inside. OSB with substructure approx. 6 - 8 cm with insulation. It is intended to become a small cozy hobby workshop for the father, where he can quietly listen to music and also have a beer while tinkering.

Ask a carpenter. I would use formwork boards there.