There is a slide about Narwhals and Ibis here (a recording of a talk from PyData Berlin 2025): https://youtu.be/qOJiQtqI348?t=2496 TL;DR: It doesn't have to be Narwhals vs. Ibis because Narwhals supports Ibis.

Update: Here's a benchmark as well, but it may be outdated: https://www.kaggle.com/code/marcogorelli/narwhals-vs-ibis-ov...