If your component library is not constrained to using Vue 2 you might want to take a look at Vue Composition API to share functionality (methods + reactive state) between different components.
Mixins might not be what you really want to be using because you kind of lose information as to what features/props/methods really will be put inside your component without re-checking the
mixin code. You also might run into issues when component options get merged by Vue at runtime. Check out these posts for more information:
As for sharing
props: What I’ve seen just yesterday (but not yet tried!) in a talk by John Leider – creator of Vuetify – is create a function that returns the props you want to reuse between components. Then you just call said function inside your props definition and use the spread operator.
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