I'm waaay behind on making all my newest betta's their own plastic mesh hammocks. I've seen the ideas of sandwhiching moss between two layers of mesh, but felt that wasn't as visually appealing, so I opted for just setting the moss inside the hammock after placing it in the tank.
Eranikus is my green dragonscale betta and he absolutely loves wriggling through the roots of my anubia I have in his tank, and so figured moss in his hammock would be a plus ~ once he decides he likes it, which I think he will ^^
Although after this video I added two pieces of polished sea-glass to weigh the moss/weed down a bit more so he has more room in the hammock and won't push it out. All in all I think it's a win-win =)