[SalesForce] Pre Select Rows in Lightning Data Table

There is no two-way binding, the rows you selected won't be in selected-rows={selectedRows} . You have use onrowselection attribute on datatable.

<lightning-datatable
        key-field="Id"
        data={homes}
        columns={columns}
        selected-rows={selectedRows}
        onsort={sortColumns}
        sorted-by={sortField}
        sorted-direction={sortDirection}
        hide-checkbox-column={hideCheckboxes}
        onrowselection={getSelectedName}>
        resize-column-disabled=true>
</lightning-datatable>

and in JS store it somewhere like :

getSelectedName(event) {
            const selectedRows = event.detail.selectedRows;

            for (let i = 0; i < selectedRows.length; i++){
                 if (!selectedId.includes(selectedRows[i].Id))
                 selectedId.push(selectedId);
            }


        }

Set a default attribute for each:

@track sortBy = 'status';
@track sortDirection = 'asc';

Then call the sort function in the wire handler:

@wire(getCases) caseList({error, data}) {
    this.caseData = data;
    this.sortData(this.sortBy, this.sortDirection);
}

P.S. you can remove the parameters by using them directly:

sortData() {
  let fieldName = this.sortBy;
  let sortDirection = this.sortDirection;

And it's also highly more efficient to simply copy the array instead of JSON round-trip:

let parseData = [...this.data];