Always remember that in fashion and aesthetics is all a matter of balance.
So If your face is round, your eyebrows must be angled. Depending on the size of your eyes and their separation, they can be more or less angled, and it will also depend on your personality.
If you have a vibrant and overwhelming personality, you will surely feel more comfortable with eyebrows well angled, while if you are calm and relaxed you probably have better eyebrows with a soft angle (but angle at the end).
What you must avoid at all costs is two types of eyebrows: the straights, which will give greater horizontality to your face; and the round, which will highlight the curves of the frame of your face.