Workspace matrix organization

I’ve recent migrated from gnome desktop.
In gnome I had a extension to organize my workspaces in a matrix-like form
After a quick search I found out that gnome-tweaks-tool is not supported.Instead, Budgie has its own.
There is something similar on Budgie? How can I install extension for my desktop interface?

Starting with the second question: on Budgie, they are called applets. In Budgie Settings, you’ll find a number of them which are installed by default. From the main menu, you can access an additional list of applets to install. Currently, there isn’t one to set a workspace matrix though.