Is it sufficient to maintain kinship ties via WhatsApp or messages when there are reasons that lead to discord and aversion, especially since direct communication causes extreme embarrassment?

Your dislike of the abominable acts your paternal aunts commit is a sign of faith. If you can bear with them and maintain kinship ties by visiting them and advising them kindly, that would be more appropriate and better. This is supported by the saying of the Prophet, peace and blessings be upon him: "If you are as you say, then you are feeding them hot ashes, and you will continue to have a supporter from Allah against them as long as you remain in that state."

However, if you fear harm to yourself, then there is no blame upon you for not visiting them and suffice with maintaining kinship ties through other possible means, such as WhatsApp messages, while being keen on advising them and striving for their reform. Also, pray for them frequently for good.