el-table-column type=selection表头全选用文字展示

el-table添加 :header-cell-class-name="cellclass"

methods中

  cellclass(row) {
            if (row.columnIndex == 3) {
                return "kkkk";
            }
        },

style中

.el-table ::v-deep .kkkk .cell .el-checkbox__inner {
    display: none;
    position: relative;
}
.el-table ::v-deep .kkkk .cell:before {
    content: "展示文字";
    position: absolute;
    right: 11px;
}