The result data table supports only vertical virtual scroll, if the resultset has a large number of columns, the memory consumption would increase significantly and cause laggy issues.
The virtual scroll should automatically work in both directions, vertical and horizontal.
At the moment, the customized virtual scroll table component is built on top of vuetify v-virtual-scroll which supports only vertical direction.

https://nhn.github.io/tui.grid/latest/ is a good candidate to replace the customized component.
Example: https://codesandbox.io/s/tui-grid-vrtmjj
However, building a virtual scroll component from scratch seems to be a better idea instead of relying on 3rd party library.