Even the 7-Zip Theme Manager http://www.7ztm.de/index.php?cat=01_English cannot add
Shell Context Menu' Icons!
Now that I search more on this Forum, I realized that the 7-Zip Developers
will Not add 'Shell Context Menu' Icons!
Simply, because they do NOT care for what hundreds of 7-Zip Users have requested for!
-This Forum is Full of Posts of Users requesting 7-Zip 'Shell Context Menu' Icons!
-This Forum is Full of Posts of Users requesting NEW 7-Zip Icons!
Neither 'Shell Context Menu' Icons, nor NEW 7-Zip Icons happened!
The 7-Zip Theme Manager cannot add the icons because it's not a feature coded into 7-Zip in the first place (the manager just replaces icons already there, and can't add new ones).
Yes it's a pity the feature has never been added. If it really bugs you, use WinRAR. Since they're a for-profit company they are financially motivated to build features that people want. Open-source developers don't have such a motivation normally.
Come on now!
How much does it cost for the 7-Zip developers
to Bring Back the 'Context Menu' Icons?
Just to remind you that old versions used to have 'Context Menu' Icons!