Modifying Webform checkbox markup
Well, solution was to remove "fake" label and wrapper div which was moved upper to wrap "control-label". All done in THEME_NAME_checkbox(&amp;$variables){}.

    &lt;div class="form-item form-item-submitted-payment-methods-1 form-type-checkbox checkbox"&gt;
&lt;label class="control-label" for="edit-submitted-payment-methods-1"&gt;
    &lt;div class="checkbox"&gt; &lt;!-- Remove this and add it as suffix/prefix for the element --&gt;
        &lt;label&gt; &lt;!-- Remove this also --&gt;
            &lt;input type="checkbox" id="edit-submitted-payment-methods-1" name="submitted[payment_methods][1]" value="1" class="form-checkbox checkbox require-one-edit-submitted-payment-methods"&gt;
            &lt;span class="checkbox-material"&gt;&lt;span class="check"&gt;&lt;/span&gt;&lt;/span&gt;
            In cash (to a member or representative)
        &lt;/label&gt;
    &lt;/div&gt;
    In cash (to a member or representative) &lt;!-- Duplicate and should be removed: how to? --&gt;
&lt;/label&gt;