Uniform is set by activating the...Quartermaster options at the War Planner's desk, I believe. This just sets outfits, not weapons. Once you've researched loadouts via HQ, and you have an armory at the outpost, you can use the "Manage Soldier" activation option on a soldier to choose a specific loadout for that soldier. Loadouts do affect the weapons the soldiers carry. Note: some loadouts require the soldier to have reached a minimum level (e.g. Medic requires a L3 soldier) and some loadouts require alliances with other factions.
You don't generally "Move" regular settlers to outposts. You use the Recruitment Clipboard to conscript them as soldiers and then choose the outpost to which to send them. Once they're soldiers, though, you can use the "Move" command in workshop mode to move them from one outpost to another. ("Outposts" are basically built upon the raider outpost functionality that NukaWorld introduced. As a result, they're not regular settlements.)
Since Outposts aren't regular settlements, you don't have all of the plot options available. Basicially just Martial and Municipal, through you really don't even need the Municipals. Outposts will automatically be connected to the supply network (scrap, supplies, food, water) if there's a nearby settlement with a caravan plot. Outposts will also automatically receive network power if your grid is running a surplus. You don't even need a Power Transfer plot, but you do need a Municipal Power Pole/Switch from the SS2 > Power workshop menu.
Outposts can use city plans, but they have to be Outpost city plans. I think SS2 only includes those for the Castle, Warwick Homestead, and Spectacle Island. Others have started to release Outpost city plans on the nexus. Build a City Planner's desk and assign a settler to be able to choose/implement an Outpost city plan.
