In checkout_index_index.xml

    <item name="validation" xsi:type="array">                                                                        
        <item name="min_text_length" xsi:type="number">10</item>                                                                         
        <item name="max_text_length_phone" xsi:type="number">15</item>                                                                        
        <item name="validate-number" xsi:type="number">0</item>                                                                    
    </item>

and then in vendor/magento/module_ui/view/base/web/js/lib/validation/rules.js

    "max_text_length_phone": [ 
            function (value, params) { 
                return !_.isUndefined(value) && value.length <= +params; 
            }, 
            $.mage.__('Phone number cannot exceed 15 characters.') 
        ], 
the above code is for validation text and for adding regex as we require, so in our case this (number with hypens allowed with max length of 15)
For, that in Magento_Ui/web/js/lib/validation/rules.js

    "validate-number": [
            function(value) {
                return utils.isEmptyNoTrim(value) || (!isNaN(utils.parseNumber(value)) && /^[0-9-\s]+$/.test(value));
            },
            $.mage.__('Please enter a valid number in this field.')
        ],
That's it, we've done it.
hope this would helps somebody.