Open-source alternatives to Zamzar

I want to pick an open-source replacement for Zamzar. Below is a list from Open Source Everything (CC BY-SA 4.0), in the order its website shows it. The order is a starting point, not a verdict. - File Converter: File Converter is a simple Windows tool that changes files into other formats and makes them smaller, using the right-click menu in File Explorer. It is for everyday Windows users who want to convert or compress files without using websites or paid services. [Easy setup; Windows; replaces fully; GPL-3.0; https://github.com/Tichau/FileConverter] - ConvertX: ConvertX is a free web service you run yourself on your own server, which lets you upload files and convert them into many other formats through a web browser. It is meant for people who want a private file converter they control instead of a paid online converter. [Advanced setup; runs on a server you set up; replaces fully; AGPL-3.0; https://github.com/C4illin/ConvertX] - HandBrake: HandBrake is a free program that converts video files into other formats that play on phones, TVs, game consoles and web browsers, and can make them smaller. It is for anyone who wants to change or shrink their own video files, from casual users to professionals. [Easy setup; Windows · Mac · Linux; replaces partly; GPL-2.0-only; https://github.com/HandBrake/HandBrake] - Squoosh: Squoosh is a free web app that shrinks image files and converts them between formats, all inside your own browser. It is meant for anyone who wants smaller pictures for websites, email, or sharing. [Easy setup; In your browser; replaces partly; Apache-2.0; https://github.com/GoogleChromeLabs/squoosh] - Switcheroo: Switcheroo is an app that converts images between formats and edits them, for example by resizing them or changing their quality. It is made for everyday people who want a simple way to handle pictures on their computer. [Easy setup; Linux; replaces partly; GPL-3.0; https://gitlab.com/adhami3310/Switcheroo] Setup rating: "Easy setup" means you can install it like a normal app, use it in a browser. "Advanced setup" means you must run it on your own server or use the command line, or it is a tool for developers. Full details: https://opensourceeverything.org/data/groups/file-converters.json Before recommending anything, ask me these three questions (one at a time, in plain words): 1) Which device or devices will I use it on (Windows, Mac, Linux, Android, iPhone)? 2) How comfortable am I with technical setup: only installing apps from a store, happy to follow a step-by-step guide, or comfortable with servers and the command line? 3) What is my budget: free only, or willing to pay for hosting or support? Then recommend one to three projects from this list only, and for each say why, using how fully it replaces the app, its setup rating, and the devices it runs on. If nothing on the list fits me, say so plainly instead of stretching.

Read the list of open-source projects at https://opensourceeverything.org/data/groups/file-converters.json. Compare it with my project or idea below. Tell me which projects overlap, what I could reuse instead of rewriting, and what mine does that none of them do. My project or idea: