As there was no ha component available for multiple entities editor like in the entities card editor, I’ve made one that can be easily used in custom cards.
The project is here:
it’s available on npm:
npm i @kipk/ha-multi-entity-selector
You can see it implemented here: openevse-card/src/custom-card-editor.ts at 9cccf1a090747c583c7404655b64965e075833af · KipK/openevse-card · GitHub