type PropertyNameNonComputed = Identifier | Literal;
type PropertyNameComputed = Expression;

interface ClassPropertyBase extends BaseNode {
  type: AST_NODE_TYPES.ClassProperty;
  key: PropertyNameNonComputed | PropertyNameComputed;
  computed: boolean;
  // ... other props
}

interface ClassPropertyNonComputedKey extends ClassPropertyBase {
  key: PropertyNameNonComputed;
  computed: false;
}

interface ClassPropertyComputedKey extends ClassPropertyBase {
  key: PropertyNameComputed;
  computed: true;
}

type ClassProperty = ClassPropertyNonComputedKey | ClassPropertyComputedKey;