Hello, I need assistance, I would like to know how it’s possible to create a negative transition (that flashes in negative for a few seconds when the media appears) and save it as a preset for frequent use, thank you
The way Kdenlive uses transitions (or better: compositions) is not to be confused with transitions other VEs like Davinci Resolve or Adobe Premiere have as presets. Hence you cannot create a transition preset for future use.
What you can do, however, is to create a custom effect. See this part of the Kdenlive documentation. If you just use the negative effect it is not worth doing that but if you need to tweak an effect to your needs or liking, you can save it (or the entire stack) as a custom effect and use it in other projects.
Hope this helps. Reach out if you have questions …