JSFiddle - React, Tailwind, and code Playground
HTML
<select name="table1" id="table1">
<option value="cacis">cacis</option>
<option value="racis">racis</option>
<option value="lalal">lalal</option>
<option value="lalala">lalala</option>
</select>
<br />
<select name="table2" id="table2">
<option value="racis">racis</option>
<option value="cacis">cacis</option>
<option value="lalal">lalal</option>
<option value="lalala">lalala</option>
</select>
JavaScript
$("#table1").change( function() {
cars = $("#table1").val();
$('#table2 option').each(function(){
if($(this).val() == cars){$(this).attr('selected', 'selected')}
});
});
$("#table2").change( function() {
cars2 = $("#table2").val();
$('#table1 option').each(function(){
if($(this).val() == cars2){$(this).attr('selected', 'selected')}
});
});