§Inkscape
§Install Theme
Download using the GitHub .zip download option and unzip them to your User themes folder, in my case /home/<user>/.local/share/themes.
§Install Icons (optional)
Download using the GitHub .zip download option and unzip them to your User themes folder, in my case /home/<user>/.config/inkscape/icons.
§Activating theme
Go to Edit > Preferences > Interface > Theme and change the theme and/or icon theme.
§Credits
The themes are avaliable in GTK Dracula Theme