Unfortunately, nothing has been said on those evolution methods, but I believe that there will be new methods to evolve them, because we already have new methods on evolving alolan pokemon (to evolve pikachu into alolan raichu, you must feed him those pancakes you found in the resort that is located on Terajuma island), but as I said we don't know about this for sure (it could technically happen that those pokemon you are talking about won't be featured in V13 and will rather be available V14 or later versions :D). So the only thing we can do is sit and wait for V13 release. Those evolution methods will probably be featured in patch notes alongside with the release.
Also, I'm sure that all devs are glad and happy about your kind words :)