Here is a list of software and websites with a feature description and how they differ from other similar products. I do not give star ratings as every tool is useful, but not every tool is the most useful for your situation.
This pomodoro timer is website based and features a cute cat image which blinks while you work. The cat will also meow when a timer ends. I consider these good things, but I will also give caveats. It places the timer in the title bar, so OBS wills truggle capturing it properly. A dosplay capture will work, but that is deffinately not ideal if you lack screen space or prefer to have your main application full screened. The time it counts down cannot be changed by the average person.
This browser based Pomodoro timer has a welcomed list of customizations you can do. If you wish to show this on stream, you can chromakey the background easily and place it on your overlay. It will, however, need a display capture as the timer is in the title. The sounds are nice and clicky.
This works on mobile and as a browser extension. It is able to block websites while you work and does not change the title of your browser window so you can use window capture with OBS. You may login to sync and track your effort. The time settings are the arrows next to the remaining time.
This uses Lua script. It is simple to setup and to use and looks wonderful. It does not use the browser at all. There's no social aspect, but you can customize it with CSS or the built-in text editor within OBS. I wish it had a skip to next segment button. I also wish it showed what phase it was in all the time. If you understand Lua, you can improve upon this.
This is the one I currently use and the intructions are at the link. It is ideal for OBS, imho. Just customize it before you run it since it'll reset each time. You can change the font within the uri (look for font= it is in 2 places). I like to use Calibri, but have fun with it. Also, you can either invoke it within OBS or use it as a browser source and do it there.
A task list using your Microsoft account. I find its features are pretty good, and it has dragging like with Trello but it kept double posting when I hit enter. I'm not sure what caused that, but I disabled my extensions and it still happened.
A project tracker that has a free version and paid version. The free version is using the template most are familiar with. Just mark the sections 'Brainstorming, Started, Tested, Completed' for example. Use the colored tags to show the categories and drag them across the sections as you reach completion again for example.
A dedicated Note taking application that can also be used to track progress on a given project. There is a mobile version.
Another notetaking application that can be used as a tracker with some adjustments. Now it has a file size limit for the free version, so it might give you a bit of trouble when working with a lot of data. There is a mobile version. Syncing isn't part of the free service anymore.
Has many useful features and accepts imports from the 2016 version. I find this very useful for worldbuilding and planning out stories. I miss the 2016 version, so you may want to see which you prefer.
Add a lot of amazing features to your windows desktop environment. I use the Fancy Zones everyday. It lets me define areas on my 2 screens where applications are placed.