Neos Wiseman is a 'cannot be special summoned except by' monster. That means his listed summon text is the only way he can ever be summoned, and can only do it while he is in your hand.
You are unable to discard him then use Monster Reborn. Also even if he is properly special summoned first, he still can't be special summoned by Monster Reborn, unlike monsters who say 'can only be special summoned by'.
Neos Wiseman says it cannot be Normal Summoned or Set. A Tribute Summon is a kind of Normal Summon, you cannot do this to summon Neos Wiseman. The only way it can reach the field is by following the text on the card.
No. A Fusion Monster cannot be summoned from the graveyard unless it was properly special summoned first. Normally this would be Fusion Summon - the only exception are Fusion Monsters who can't be fusion summoned, like the Neos and XYZ fusions. All you need to do for those is follow their text, for them to be properly summoned. Either way, a Fusion Monster placed straight into the graveyard by Fusion Guard cannot ever be special summoned from the graveyard by any method.
No. The Neos Fusion Monsters that use Neo Spacians can ONLY be Special Summoned by "Contact Fusion", meaning the fusion material monsters must be on the field and are sent to the Graveyard to Special Summon the monster.
No it does not activate, Neos Wiseman will be sent to the graveyard before it's effect can activate. So you won't receive any Life Points, nor will your opponement lose any.
If the E-Hero trying to be Fusion Summoned requires a nonspecific E-Hero (such as "E-Hero Absolute Zero), then "Neos Alius" can be used. If the Fusion Monster requires "E-Hero Neos", "Neos Alius" cannot be used since its card name cannot be treated as "E-Hero Neos" while in the Graveyard. (Though this only applies to "Rainbow Neos" who actually is not a E-Hero fusion monster.)
Rainbow Neos 'cannot' be special summoned except by Fusion Summon of the listed components. There is no way around this, not even cards like Metamorphosis or Cyber Stein.
Yes it defenitely would, if your opponements field is filled with monsters and you equip it to Neos Wiseman, you can do some serious damage and gain some Life Points as well.
Almost, if not all Elemental Hero Fusions say "This card cannot be special summoned, except by Fusion Summon". This means the only way it can ever hit the field is by Fusion Summon. Some monsters say "can only be special summoned by.." and this listed method is just for the initial summon from hand, if you do this properly, you are allowed to resummon them from the graveyard with cards like Monster Reborn. However, the 'except by' monsters are different, even if you properly special summon them, you still can't revive them from the graveyard like this. Because of that, Elemental Hero fusions are not valid targets for Re-Fusion, as it does not 'Fusion Summon' them.
Yes, "Future Fusion" can be used for "Rainbow Neos" by sending an "Elemental Hero Neos" and a "Rainbow Dragon" or "Dark Rainbow Dragon" from your deck to the Graveyard.
It's very good but really hard to summon
There is no card called "Miracle Contact" so:If you are referring to using "Miracle Fusion" with "E-Hero Neos Alius" (when not Double Summoned), then you can use it if the Fusion Material monsters does not call for a specificE-Hero. If the Fusion Material monster required is "E-Hero Neos" then you first need to Double Summon "E-Hero Neos Alius".If you are instead talking about using "Contact Out" on a Neos Fusion Monster and Special Summoning "E-Hero Neos Alius" from your deck, you can not since while it is in the deck it's name is not "E-Hero Neos".
Most, Elemental Hero fusion monsters say they "cannot be special summoned except by...." which means that's the only way for them to reach the field. Monsters that say "can only be summoned by" have to be initially summoned by the listed method, but after that, can be reborn using cards like Monster Reborn. But even if you use the listed method initially, the 'except by' monsters cannot be special summoned from the graveyard, by cards like Monster Reborn, or Skyscraper 2. So you'd have to look at the specific Elemental Hero's text - almost all are 'except by', a notable exception are the 'Neos' fusions.