1) This is a weak narration. We don’t consider everything that is reported as authentic. We have to assess it’s chain after insuring that it doesn’t contradict the holy Quran. We should also use our intellect.
2) We do have multiple narrations that mention the Imams prostrating at the time of their birth.
This is not necessarily difficult to believe especially when we read in the holy Quran that prophet Jesus peace be upon him spoke in his cradle fully eloquently declaring his servitude to the Almighty God
3) This is similar to the first one. In fact there is a controversy over the inception of Peacock with the tears that some have wrongly attributed to Imam Ali peace be upon him when in fact he was denying that myth
أَوْ يَكُونَ لَكَ بَيْتٌ مِّن زُخْرُفٍ أَوْ تَرْقَىٰ فِي السَّمَاءِ وَلَن نُّؤْمِنَ لِرُقِيِّكَ حَتَّىٰ تُنَزِّلَ عَلَيْنَا كِتَابًا نَّقْرَؤُهُ قُلْ سُبْحَانَ رَبِّي هَلْ كُنتُ إِلَّا بَشَرًا رَّسُولًا
or thou have a house [made] of gold, or thou ascend to heaven – but nay, we would not [even] believe in thy ascension unless thou bring down to us [from heaven] a writing which we [ourselves] could read! Say thou, [O Prophet:] "Limitless in His glory is my Sustainer! Am I, then, aught but a mortal man, an apostle?"
Not the best translation however God is telling his messenger to declare to the people that he is a human and a prophet
Obviously as a messenger of God he can perform miracles however he is still a human
4) Even in human biology there are exceptions and people with conditions that are rare or unique.
In fact I personally know someone who doesn’t get monthly periods. I also know a few people who were born without the need for circumcision as they did not have the extra skin