Installing
2. Enabling UNetbootin PPA Repo
Add UNetbootin PPA for Mint GNU/Linux
3. Installing UNetbootin
Then to Install UNetbootin in Linux Mint.
sudo apt install unetbootin
4. Running UNetbootin
Finally, Launch & Enjoy UNetbootin
From Desktop Make Use of the Launcher:Or from Shell with:
sudo unetbootin
On Startup you’ll be Prompted to Insert the Admin Pass…

So Now I’m truly Happy if My Guide could Help you to Install UNetbootin on Linux Mint 19!