I will translate the mantras in due course of time.

Namaste, my heartfelt thank you to all of the learned and divine people here who put in their time and effort to guide us. I have a humble request to please help me find the correct way to do the Sarvayonimudrā.

Namaste. Thank you so much for sharing the Shri Kamakhya Sahasranamavali. May Maa Kamakhya bless you with wisdom, peace, and prosperity. I humbly request you to kindly share a Mantra for Maa Saraswati, including Viniyoga, Nyasa, and Dhyana. It would be a great blessing for spiritual practice. Thank you.

Some old publications of the Kanchi Mutt have this scripture. I have a copy of it in Telugu, so it does exist! I am prohibited from sharing, unfortunately.

They are the same. Different attributes of the same deity.

For those struggling with sexual energy here's a most secret Taoist practise revealed out of compassion by the great master Osho. The technique might look simple but as Buddha says एहिपस्सि-को: try and see for yourself. It is from a rare Taoist treatise called The Secret of the Golden Flower, for anyone interested in exploring further I highly recommend reading Osho's 2 volume commentary on it. "Conservation of energy is a meditative process. It is not moralistic. I will suggest a small method to you that will be of immense help. It has been used by Taoists down the ages. It is given only from the Masters to the disciples; that's why it has not been written in the books. But now the time has come that it should be given, because now millions of people are working on their spiritual search THROUGH books. Masters are not so available either. This is a simple method of transforming your energy and leading it upwards. And always remember, Taoist methods are very simple, so don't think, "How can such a simple thing be of such great importance?" Practice it, experiment with it and you will know. The process is: At least twice a day -- the best times are early in the morning, just before you get out of your bed. The moment you feel you are alert, awake, do it for twenty minutes. Do it first thing in the morning! -- don't get out of the bed. Do it there, then and there, immediately! -- because when you are coming out of sleep you are very very delicate, receptive. When you are coming out of sleep you are very fresh, and the impact will go very deep. When you are just coming out of your sleep you are less in the mind than ever. Hence some gaps are there through which the method will penetrate into your innermost core. And early in the morning, when you are awakening, and when the whole earth is awakening, there is a great tide of awakening energy all over the world. Use that tide; don't miss that opportunity. All ancient religions used to pray early in the morning when the sun rose, because the rising of the sun is the rising of all the energies in existence. In that moment you can simply ride on the rising energy wave; it will be easier. By the evening it will be difficult, energies will be falling back; then you will be fighting against the current. In the morning you will be going with the current. So the best time to begin is in the early morning, immediately, just when you are half-asleep, half-awake. And the process is so simple. It needs no posture, no yogasana, no bath is needed, nothing. You simply lie down, as you are lying down in your bed, on your back. Keep your eyes closed. When you breathe in, just visualize great light entering from your head into your body, as if a sun has risen just close to your head -- golden light pouring into your head. You are just hollow and the golden light is pouring into your head, and going, going, going, deep, deep, and going out through your toes. When you breathe in, do it with this visualization. And when you breathe out, visualize another thing: darkness entering through your toes, a great dark river entering through your toes, coming up, and going out through the head. Do slow, deep breathing so you can visualize. Go very slowly. And just out of sleep you can have very deep and slow breaths because the body is rested, relaxed. Let me repeat: breathing in, let golden light come into you through your head, because it is there that the Golden Flower is waiting. That golden light will help. It will cleanse your whole body and will make it absolutely full of creativity. This is male energy. Then when you exhale, let darkness, the darkest you can conceive, like a dark night, river-like, come from your toes upwards -- this is feminine energy: it will soothe you, it will make you receptive, it will calm you, it will give you rest -- and let it go out of the head. Then inhale again, and golden light enters in. Do it for twenty minutes early in the morning. And then the second best time is when you are going back to sleep, in the night. Lie down on the bed, relax for a few minutes. When you start feeling that now you are wavering between sleep and waking, just in that middle, start the process again, and continue for twenty minutes. If you fall asleep doing it, it is the best, because the impact will remain in the superconscious and will go on working. And after a three-month period you will be surprised: the energy that was constantly gathering at the MULADHAR, at the lowest, the sex center, is no more gathering there. It is going upwards. If you do this simple method for three months, you will be surprised: there is no need to repress. Transformation has started happening."

It is a Sanskrit scripture that exists as a manuscript in the old Telugu script. The current published versions of the same scripture are also in the Telugu script. There are no English or Devanāgari versions available at this time. It has a collection of most of the Āmnāya mantras. Some others are in the Saptaviṃśati Rahasyam and many other minor Āmnāyas are in the hidden Bimbāmbika Bodha, Mahāvaḍavāṇala tantra etc.

In due course of time if I am able to translate it, I will certainly share it here.

You need to follow the Kālī krama and for that, you must seek a guru who is well versed in that tradition. I honestly do not have any references that I can provide you, but you should explore it to the best extent possible.

The mantra referenced in your google document and this are the same. I don't really understand your question. In general, there can be different variations in the Viniyoga etc and the mantra can still be the same. This is due to differences inherent in various traditions. You simply need to follow the mantra that you are initiated in. Nothing wrong in gaining knowledge, but let is be specific to the path that you are following.