The following character can become LR by Dokkan Awakening. Summon rates for them are however very low, and we don't recommend you to aim to get them.
Mystery Super Technique Super Saiyan 3 Goku
Dokkan Battle Reroll Tier List
INT UR Characters
Goku [Daily Training]
HERO Extermination Plan Evil Powers Strike Back
[Reign of Terror] Frieza (1st Form)
[Emperor's True Splendor] Golden Frieza (Angel)