Someone else asked a similar question not long ago. This was my response:
To my knowledge, all aquatic plants can get nutrients from their leaves and their roots. Given this, it is usually easiest to offer fertilizers in the substrate and the water column. So, I would say use root tabs and liquid fertilizer.
Here is a good article on this from the 2Hr Aquarist:
Water column was sufficient for java ferns and anubias because they aren’t planted. Once I have planted plants it is my understanding I should use root tabs as well. Thanks pp for the article!
Very good article