I just thought of something, if I do the covering with glue, then the tissue will get sticky because of the high humidity here.
But I just remembered that there is something used to seal wood - "sellador" "wood sealant formulated with nitrocellulose resin. Bingo, nitrocellulose is what makes up dope. It's kinda brown-looking, and usually needs to be thinned out a lot. When it's dry it's very sandable, and it can be reapplied in several coats.
But, as far as being smelly, to me it just smells like thinner. Dope is reported to have a very unpleasant smell.
I don't know if it will tighten the paper like dope should. I'll see if I can get my hands on some "sellador" and try that out.