It was hard to find documentation on this, but it is possible by using sortingDataAccessor
and a switch statement. For example:
@ViewChild(MatSort) sort: MatSort;
ngOnInit() {
this.dataSource = new MatTableDataSource(yourData);
this.dataSource.sortingDataAccessor = (item, property) => {
switch(property) {
case 'project.name': return item.project.name;
default: return item[property];
}
};
this.dataSource.sort = sort;
}