I have repaired a few tyres like this. Sealant normally does the job with small holes but i seem to be a bit of a rear tyre killer so have had to learn to repair them or be very broke 🙂
If i am out on the trail i use these Tubeless Repair, they work very well and if you follow the instructions they will last the life of the tyre.
I f for whatever reason you need to repair a tyre at home i use this procedure, the second one 🙂 Patch repair.
Oh i found a great tip online the other day, use wetsuit glue on the outside cut after you have repaired it, that type of glue is not brittle and moves with the tyre but holds its integrity, just for a bit more bonding.