When adding a stroke to a frame, it would be nice to be able to only apply that stroke to just one side or multiple sides of the box without it being the whole thing.
Suggest you vote there
I really need this too. It’s a pain in the neck when designing tables.
You can use a plugin called Border (Figma - Border | Quickly add single borders in Frame. Usage: 1. Open 'Border' from the plugin menu. 2. Select one...) which does this by adding a layer group to the edges of the box. It works great except that it’s limited if you need to add corner radius