Yes. Chromatic aberration can still affect a black-and-white image, even when the colored fringes disappear.

The key issue is that different wavelengths do not focus at exactly the same point. In a color image, that mismatch appears as colored edges. In black and white, the color difference is removed, but the underlying focus mismatch can remain as slightly softer high-contrast edges or a faint loss of crispness.

This is because each color channel may form a slightly different image size or focus distance, so only one part of the spectrum may be perfectly sharp while others are a little out of focus. When converted to monochrome, those differences are merged into tonal values rather than visible colors.

So: black-and-white conversion can hide the obvious fringing, but it does not necessarily eliminate the sharpness loss caused by chromatic aberration.