Fire Emblem Guilds?

Since this is a mobile game, I've always wondered how multiplayer integration would work. Whether it's through a guild (chatboard, etc.) within the app. However, the only instance of multiplayer is the Arena (Rivals Domain, etc.) and even then it's not genuine multiplayer in the sense that you're interacting with another person.

I've always tossed the idea of guilds in Fire Emblem Heroes for several reasons but right now I can only think of 2:

1, it could open up the possibility of trading units.

2, you can interact with other players without the need of extra chatboards/forums.

While trading units might seem like a bad idea, it could be implemented properly. Examples being; that accounts have to be linked to Nintendo in order to trade, accounts would have to exceed a specific age (to avoid players making new accounts), and that certain units can't be traded (Askr units obviously, but GHB units and other units deemed vital could also fall under this category).

Though trading without repercussions would seem a little too easy. Maybe putting restrictions (like being able to trade once a day) and using the Arena Medals as currency could also slow down the pace of units being tradied. More Arena medals would be needed for stronger units.

While also adding that small feature that's in Grand Conquests to your guild would also entice people to join guilds. A feature that would let you "Ask for Help!" by displaying a small button under your name that needs at least 10 different players to click on it. Once 10 different players from your guild click it, you get a random reward (1 Orb, 5 Refining stones, 5 Sacred Coins, etc). This little feature would be allowed once per day, and the rewards cycle, so you don't abuse it every hour and everyday you get something different.

I know it's really unlikely FEH will ever introduce a multiplayer mechanic like this, but what's everyone's thoughts on it?