Don’t know, ask Google 
I don´t use Google for these kind of things I use Microsofts Copilot instead and it answered this on my question if Gaudui is responsible for the top decorations even on the older part of the church:
" Yes, Antoni Gaudí did design the decorations for the older towers of the Sagrada Familia. The Nativity Facade, which includes some of the older towers, was directly overseen by Gaudí himself. He incorporated intricate details and religious symbolism into these towers, reflecting his unique style and vision12.
The decorations on these towers include a variety of elements such as sculptures, mosaics, and inscriptions, all meticulously crafted to convey religious themes and enhance the overall aesthetic of the basilica12."
Please click on the link too. There you will find another picture of the church that really gives an impressive overview. It is truly a very special piece of architecture.