I created a legend in the print composer and the default layer orientation is
How can i change the legend elements orientation like in ArcGIS?
I seeked in the Item properties but didn't found any hint.
I don't think this is currently possible as there is already an existing ticket which was updated a year ago:
I think Joseph is right, there doesn't seem to be a way. Found a couple of workarounds. Vesanto's suggestion of using a separate text box for your labels, and removing the labels from the legend, is also worth looking at if you want to stay in QGIS.
Edit in inkscape
If you're familiar with InkScape, you could
Here's an example:-
You might find you need to experiment a bit to get good results, especially with SVG. And if using Inkscape, remember to add in a background as the default is transparent.
Just for fun I found a workaround. It's not practical and the results don't look too professional ;-)
use one of the many 'flip and mirror text' sites. These convert text to upside down equivalents (really, unicode characters will look similar to upside-down and/or back-to-front characters). For example this site
edit each legend item, copying and pasting the rotated text in. Make sure you choose flip AND mirror.
set legend rotation to 180 degrees
This will only work with basic Latin characters (e.g. English A-Z and 0-9). It will not work on all fonts; you'll need to use one of your system fonts which has good unicode support. Also, your legend will appear at the bottom...
There are plenty of upside-down fonts on the web, but not seen any which are also mirrored. If you can find one this might almost work..