Here’s a solution that works for all platform and versions of Chrome
1. Install Stylist Extension.
2. Click SETTINGS in chrome
3. Click EXTENSIONS
4. Find the stylist extension and click OPTIONS
5. Click STYLES
6. Click ADD NEW STYLE
7. Copy & paste the following:
- A:visited { color: red ! important }
8. Name the style
9. Click the ALL SITE check box
10. Click SAVE
11. Find a page with visited link, refresh, and you’ll see the new color.
You can find colors you like here: CSS Colors, and use code like rgb(255, 0, 0) in place of red
Source: https://support.google.com/chrome/forum/AAAAP1KN0B0sVkgKCIxyaM/?hl=en&gpf=%23!topic%2Fchrome%2FsVkgKCIxyaM