Someone named their daughters: Avigail and Avichail. Both used “Avi” for short.
In your case, the issue would arise if both mother and daughter are called Sheva for short. If that is the case, it can lead to confusion and issues of Kibud Aim. They would require a shinuy to avoid this.
A shinuy is even when there is a second name, as between mother-in-law and daughter-in-law, although the “added” name should be first. The shinuy should actually be used.
In your case, the distinguishing “prefix” is first and therefore (if the complete name is used for one of them), there is no chishash.