The trick is to perform your "X input" action on the TestStepValue for the Link element rather than the table cell itself. You can use table steering to navigate to the link element.
You'll first need to have a module attribute for a link element within the cell module attribute of the table you are steering. As long as the target cell contains only one link element, you won't need to worry about it being uniquely identifiable. In fact, any identifying attributes on that module attribute must be generic enough to match any link in the table that you might want to steer this way.
For example, if your table looks like this:
<table>
<tr>
<td>Some data</td>
<td>Some more data</td>
<td>
<a>Link element in another cell</a>
</td>
</tr>
<tr>
<td>Some data</td>
<td>Some more data<td>
<td>
<a>Link to be clicked</a>
</td>
</tr>
</table>
Your Module needs a Table module attribute with a structure similar to below:
Table
Row
Cell
Link
You can either scan the link and drag & drop it into the cell module attribute. You can also add a link element to the cell by selecting the link icon from the context menu of the cell module attribute. This link to Tricentis documentation has a good visual:
https://documentation.tricentis.com/en/1110/content/tbox/type_table.htm#Definingcontrolsincells
Then, assuming the target link is the third cell of row #2, our test step would navigate to the link in that cell, and perform the X input action on the link module attribute.
Name Value Action Mode
Table {NULL} Select
$2 (Row) {NULL} Select
$3 (Cell) {NULL} Select
Link X Input
Basically, you'll step your way to the target link through a chain of 'Select' actions. Then, you can perform the input action on the isolated link element.