Elohim by itself, Gods, -im is plural termination, usually masculine, but many modern Jewish scholars use it to demonstrate both the plurality of gender and non-gender of God in Antiquity among early Jewish communities due to its use in Genesis 1.
Bene ha Elohim, which is what is in Genesis 6 actually says, is how we derive gender: Sons of the Gods.
The details of how Angels (and Demons, or Djinn, thereby) have sex is a hot topic for a very long time, with a wide variety of issues. Some insist it is not that the Sons of God had gender inherent upon them but rather they had the capacity to take flesh; some interpret the latter to mean they possessed men or that they literally created bodies from earth like neo-adams.
Islam is complex because various groups have argued various things. Most Shia jurisprudence maintains that gender is actually determined by the soul, not the body, and thus someone who is gay is “actually” a woman inside a man’s body, and thus they are encouraged (or obligated, depending on the historical moment) to transition to being a woman.
Otherwise, many take the linguistic approach, so for example some words for Soul (ruh aka Spirit/Breath/Soul, analogous to the Jewish Ruach, which became equivocated with the Greek Pneuma, which is the “Living” Soul/Spirit) is and can be either masculine or feminine, other words used (e.g. Nafs aka Self, analogous to Jewish Nephesh, which became equivocated with the Greek Psyche, the Rational Soul) is often monogendered.
The nature of paradise for Islam is complicated because while there is “wine” in Paradise, the wine doesn’t get you drunk, so it it’s spicy grape juice at best, because the nature of wine is the getting you drunk, alcoholic part.
The lack of marriage in heaven is not because we “become like angels”, which Jesus did not say. You are referring to Luke 20, where Christ says, “because they are equal to/like the angels and are sons of God, being sons of the resurrection”. The Greek used “isangeloi gar eisin”, and isa- is not homoangeloi nor homoiangeloi, so its not a question of becoming or being like angels but rather acquiring some of their characteristics.
However, because in the resurrection we are affirmed as given perfected bodies and are all one in Christ/God, and angels are spiritual beings, we thus will have our souls and bodies perfected and be one with God, and thus there will be no death but also no marriage (or sex).
This is why I said generally, because generally most Abrahamics fall on the spectrum of “the gender of our being is not absolutely rooted in our souls” and the metaphysics of non-corporeal spirits maintains they are, well, non-corporeal but that these souls can take on bodies in circumstances.
Roman Catholicism maintains souls do not have Gender.
The use of gender for Saints is merely a historical product.
Mary is a special case because of the Assumption/Dormition, same as how Christ ascended with Body into Heaven.
