>>6002408>pic relatedObviously make sure its the matte finish one.
You could also double seal it with the gloss finish then the matte one over top that (since I've noticed gloss seals seem to hold better). I've never had to do it on my nendos or figmas though. I've only used that method on minis I've pained since they get handled a lot more.
Also, if you want some pieces or parts to stay glossy while the rest is matte like the blood i did here
>>6002348 I just seal it with matte let that dry then hand paint over the areas with a clay gloss. I use Sculpey acrylic emulsion with the matte finish (its not a very matte finish...).