Headcannons (feel free to use without credit):

Reception speeches by each nation’s head - Tonraq, Tenzin, Fire Lord - Wu intentionally left out. Maybe Suyin. Huge press event (not officially a part of the celebrations), as everyone who thinks themselves important will want to make a statement. This is *the* most powerful couple in the world.

Korra’s MoH would be Jinora, Mako/Bolin/ makes up her party.

Asami’s MoH would be Zhu Li. Varrick, Pema, make up her party.

Jinora and Zhu Li would be phenomenal at setting this up - Spirit expertise and Executive Assistance expertise.

The ceremony is held in the spirit world. Iroh officiates. This will be the first major human ‘incursion’ to the spirit world (this a wedding with hundreds neccessarily invited), and of course no wedding goes off without a hitch or two.

Varrick will have a film crew. Duh. Can you imagine the proceeds from distribution of this event? TV may come to this universe as a direct result of this wedding.

Reception is held in a Republic City Venue. NOT Air Temple Island, in deference to balance. Maybe Avatar Korra Park? or would that be too much? You know damn well this will be exactly like a Gatsby party.

4 benders from each nation will do the Avatar-version of 21-gun salute. (so, 16-bender salute) as they walk out the gate as a married couple.

Korra will wear white, maybe silver-inlaid patterns of the four nation symbols. I don’t like her in dresses, but those are usually the most expressive. Future industries can make an inlay that glows like the Avatar state when the brides kiss. (It accidentally catches fire, but Korra puts it out with air bending - water would ruin the dress). (This would be the in-joke of the wedding - 'She sets me on fire!’ 'She can’t wait to get her out of those clothes!’ 'See, i TOLD you she [Asami] was Fire Nation’) Bride’s 'maids’ can wear black suits with the accessories of their nation’s color.

Asami can wear black with white accessories - they may? also glow. I like her in a knickbockers suit. She even has the 30s golf cap, worn tilted, 'just so’. Bride’s 'maids’ can wear black suits with the Future Industries accouterments.