Its normally the other way round, by what to put them next to.
Some years back there were some suggestions 'I recall it was on Beechgrove' to place basil plants at the base of your tomato plants in the greenhouse and outside.
It really does for me make the basil grow so much better, with a better spread and a long growing season.
It always struggled when I just grew them alone in and outside before I tried that.
I suspect as just being a herb, many will plant it next to Marjoram and Oregano, being Mediterranean common herbs with pasta type dishes, for easy companion picking.
I would think planting it with other herbs may help more to do with allowing basil to keep its good drainage and to get plenty of the sun and warmth.
