I adore Smol. It comes through the post, is plastic free, vegan, cruelty free and doesn't harm marine life! The smell is a really subtle but clean fragrance as well (although you can also get fragrance free if you'd prefer)
Ecover and method are my favourites, ecover has some really soft scents and even 0% ultra sensitive x
I 2nd Smol. Plus it is delivered to your house.
Persil non bio or the aldi one x
I use Ecover zero%
If you're not wanting Fairy, see if you can try Persil Non-Bio. I need to be careful of this because of my own skin allergies to Persil and Ariel 😅 but any non-bio should be good enough to use for your baby's clothes, even knock off brands. Just make sure you don't have any skin allergies! X