JSFiddle - React, Tailwind, and code Playground

HTML

// one
<select id="s1" onchange="handleSelection(this, s2)">
    <option value="0">0</option>
    <option value="1">1</option>
    <option value="2">2</option>
    <option value="3">3</option>
    <option value="4">4</option>
</select>//two
<select id="s2" onchange="handleSelection(this, s1)">
    <option value="0">0</option>
    <option value="1">1</option>
    <option value="2">2</option>
    <option value="3">3</option>
    <option value="4">4</option>
</select>

JavaScript

function handleSelection(source, dest) {
    
    for(i=dest.length-1; i>=source.selectedIndex; i--){
        dest.options[i].disabled = true;
    }
}