Download flash tool: https://storage.googleapis.com/otas/2014/Smartphones/Aquaris_E5_HD/Ubuntu/Web%20version/SP_Flash_Tool_exe_linux_v5.1424.00.zip

Install needed dependency:

sudo apt install libqtwebkit4

Download firmware: http://disq.us/url?url=http%3A%2F%2Fstorage.googleapis.com%2Fotas%2F2014%2FSmartphones%2FAquaris_E5_HD_L%2F2.0.1_20150623-1830_bq-FW.zip%3ASJxYQYCPV0zkbNlDgbU_pSXtktk&cuid=3581332

http://a25.co/ubuntu-phone-how-to-install-android/

Then:

1. Turn off phone 2. Run flash_tool.sh

chmod +x flash_tool
chmod +x flash_tool.sh

sudo ./flash_tool.sh

3. Go to Download, select MT6582_Android_scatter.txt, choose “Firmware Upgrade”

4. Click Download and plug in the USB cable and wait for the install to complete

5. Turn on phone and wait for 10-15 min