This is a bad idea. All colours are based on their tertiary mechanincs based on this article: https://magic.wizards.com/en/articles/archive/making-magic/mechanical-color-pie-2021-10-18

DUAL COLOUR THEMES
Red/Blue: +1/+1 counters
Black/Blue: Ramp (Blue: Untap lands and treasure, Black: Permanant Mana Production)
Green/Red: Aristocats (Green: Sac, Red: payoff)
Green/White: Cast spells from your graveyard
Red/Black: +N/+N to your team (Zombie Goblin tribal)
White/Blue: Animating lands
Green/Blue: Discard as a cost
Green/Black: Friendly to artifacts

MIGHT NEED CHANGING
White/Black: Play two or legendaries?
Red/White: Zada shenigans (could be control instead?)

POSSIBLE MISC THEMES
White: Prowess, Fog, Extra attack, Counterspell, -N/-N (on spells), Hexproof, Trample, Reach
Black: Flash, First strike, Stealing permanents permanently, Trample, Permanat Mana production
Blue: Indestructible, Deal damage when blocked, Treasure creation, -N/-N (on spells), Trample
Red: Extra turns, Rewards for death, End the turn, Indestructible, -N/-N (on spells)
Green: Flying, Protection, -N/-N (on spells), Counter target activated/triggered ability

Inspiration taken from https://cubecobra.com/cube/overview/color-shifted