PS actions and brushes

https://helpx.adobe.com/photoshop/using/preset-migration.html

This covers everything including migrating between machines (manual) and when upgrading your software.

All of your personalized settings are in a specific set of folders within your Mac user account folder. Adobe lists where things are in this help article:

Preference file functions, names, locations | Photoshop

If you look through or do a search within that web page, you will find the folder locations for actions, brush presets, and many other settings. Just copy those to the new Mac, making sure to put them in the same folder location within your user account folder on the new Mac.

For example, the second item listed in the table is Actions, the second column says the filename you are looking for is Actions palette.psp, and the third column shows you the folder path to where that is stored. The next item in the table is Brushes, and so on.

You’ll find that it says many settings are in subfolders within the folder:

Users/[user name]/Library/Preferences/Adobe Photoshop [version] Settings

Edit > Presets > Export/Import Presets for example. You can also copy desired presets, compress, send to yourself via email and paste on new computer.

Syncing is discontinued Sync presets on multiple devices (adobe.com)