The best alternatives to Symbols to Copy are Dashboard UI Kit, Symbol, and Symbol Design System. If these 3 options don't work for you, we've listed a few more alternatives below.
Symbol is an advanced web-design system based on Sketch nested symbols. There are not only the components but also the logic, the atomic structure. You can easily change just one symbol to create your own desig...
Merge Duplicate Symbols is a Sketch.app plugin to merge symbols with the same name. Choose the one you want to keep and press OK. The other symbols will be removed, and all of their instances will be replaced b...
Symbol Organizer is a Sketch plugin which organizes your symbols page alphabetically (including layer list) and into groupings determined by your symbol names.