Unfortunately, it is not well documented. You would have to figure it out through the source code, but this might get you going:
Consume the UMB_PROPERTY_DATASET_CONTEXT
, a context class that holds the values of the current entity, so it would work inside property editors, workspace views, and so on:
import { UMB_PROPERTY_DATASET_CONTEXT } from '@umbraco-cms/backoffice/property';
const context = await this.getContext(UMB_PROPERTY_DATASET_CONTEXT);
const allProperties = context?.properties ?? [];
const specificProperty = context?.propertyValueByAlias('alias');
You can find properties on it and set values on specific properties – here I have two variables, the first one holds all properties and the second one holds a value of a specific property by alias.