How can I upload the image for different bylines

This could probably be achieved with some advanced theme code and one of the following plugins to associate images with taxonomies:
https://www.ads-software.com/plugins/taxonomy-images/
https://www.ads-software.com/plugins/advanced-custom-fields/

A less ideal solution would be to use HTML markup in the description field of the byline, then use the code I shared in a previous thread to display the content of the description field.

Has anyone been able to get to a working solution for custom Bylines with associated author images to replace avatars?

It seems like the best and simplest approach would be to add only the field/s you need to the Byline taxonomy itself without using a plugin. Some ways to do this:

• https://pippinsplugins.com/adding-custom-meta-fields-to-taxonomies/
• https://shibashake.com/wordpress-theme/add-term-or-taxonomy-meta-data
• https://wpdevsnippets.com/add-category-tag-taxonomy-picture/

The Taxonomy Images plugin seems to be unsupported, so I’m not sure if it’s a good choice moving forward. It was recently forked to GitHub by some users to deal with some compatibility issues after a core update to WP, so maybe it’s OK. Unfortunately I was unable to use it to display the image field values within page templates. It may work only with taxonomy term page templates or possibly the single post page template; I was trying to get it to work in a template code block that’s conditionally loaded into single.php, so that may be the problem — or else I just did something wrong.

Using Advanced Custom Fields might be the best plugin-based solution. With it and the Taxonomy add-on it looks like you could create your own Byline taxonomy and map it to posts or any other content type: https://www.advancedcustomfields.com/resources/how-to/how-to-get-values-from-a-taxonomy-term/

Sample code: https://wordpress.stackexchange.com/questions/71287/advanced-custom-fields-taxonomy-terms-images

This would be a great feature to add. I’ve been researching how to add and display more fields but haven’t had time to build/test yet.

The advanced fields plugin could be used to create an infinite number of sophisticated taxonomies. It’s pretty powerful.

Taxonomy Images works, but it seems ill-suited for displaying term images as avatars with byline names and descriptions. So far I’ve only managed to make that work by looping through an array of the post terms with get_the_terms and using a term value from there to fetch the right term image from Taxonomy Image which requires another loop through nested arrays. See https://www.ads-software.com/support/topic/querying-for-image-of-term?replies=5#post-5828450