This would require the capsule to simulate physics which would create all sort of undesired behaviours. Luckily enough, the Character Movement Component understands physical impulses:
Do note that the component is working really hard to keep the character stick to the ground. You may need to rotate that vector a bit up, use Jump, use Launch and / or play with physical materials and their friction. There are additional friction settings on the component, too. Explore it.
Here’s a wacky scenario when a character needs pushing in very specific fashion; the component’s velocity is overwritten directly: