There are many alternatives to UNetbootin for Linux if you are looking for a replacement. The best Linux alternative is balenaEtcher, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 25 alternatives to UNetbootin and 19 are available for Linux so hopefully you can find a suitable replacement. Other interesting Linux alternatives to UNetbootin are Ventoy (Free, Open Source), dd (Free, Open Source), MultiBootUSB (Free, Open Source) and MultiSystem (Freemium).
(Straight up rufus for Linux users ) The mkusb tool was developed to make it simpler and safer to create boot drives with the method to flash or clone an iso image or a compressed image file. It is using dd under the hood.