My '72ish P bass body is Paulownia and I didn't seal it as such I sanded it to 240 grit, then I just did 3 coats of under coat, flattening after the second coat then 3 top coats and the body came out flat with no grain sinkage
I suppose it depends on how thick the paper is? If its like tissue paper then you might see some grain through it but if it's quite thick then I think you should be go fine 🤔