oooh thats really cool!!
1. you could use a super light or white lip tint/stain (preferably matte finish for a better base to put stuff on top) instead of concealer, since you'll still be able to see the original colour of your lips a bit and you can add much less concealer on the lips. unfortunately i dont have any recs and i also havent seen any really light lip stain/tint around so this might be hard to find.. for me using a concealer never works nicely and it doesnt dry right, it becomes super cracky and patchy but it might work for you with a thinner layer over the lip tint/stain
2. or an even better option - i think some skin-coloured lip liners and lipsticks exist out there, youll be able to find some brands with really light nude shades or maybe mix two colours to get your exact skin colour?
3. there is always the option of just using concealer which is what a lot of people use actually! idk it just doesn't work for me probably because of my dry lips or the concealer i have is too thick but it could work for you, you never know until you try
good luck <3