These will be listed by fandom, then by crossover (Crossover characters will be grouped under what series the CHARACTER is from.)

Katekyo Hitman Reborn
avaricearco - Canon!Mammon/Viper, pre-Rain battle and post-Storm battle
bullheadedboss - Adult Lambo Personality!Tsuna for timidnebbia 's AU
crossbetween27 - Slider!Tsuna
husbandosawada - Groom!Tsuna, paired with wedding6realms 
neverbetherain - Vongola messenger!Lal Mirch for luchedevongola 's AU
relaxedsun - Yamamoto ( Read more... )