Hi, here’s a suggestion from a video of Rocksteady from Unreal Fest 2020:
it seems you could use the smesh class (c++) to import particles as 2D objects. I didn’t try it myself but it looks really cool. However, this will not spawn a particle in your scene. It will remain at the widget level but you could link it up to the position of button.
Take a look at this video:
The section you’re looking for starts around minute 14:00.
You could also check the UE marketplace to see if there’s any plugin or blueprint that allows you to do this. There are also 3rd party app that allow to design richer UI interfaces such as the tool from coherent labs.