No, it does not.
The only possible overlap, is if an effect tries to put a Synchro or Fusion monster in hand or main deck, these are returned to the Extra Deck instead, as a specific replacement effect.
If an effect tries to return a Fusion or Synchro monster back to hand or deck, they go to the Extra Deck instead.
Since August 2008, a legal Yu-Gi-Oh deck has 40 to 60 cards in the main deck. It is no longer legal to have an 80 card deck (cards in your Extra or Side Decks do not count towards your main deck size limit).
A teammate cannot use an extra deck tag during dueling. Each player holds their own extra deck and it is not possible to use another teammates for play.
Like Fusion and Synchro monsters, it will return to the Extra Deck. Any attached XYZ material will be placed in the graveyard.
Monster Recovery reads; "Unite 1 of your own monsters on your side of the field and your hand with your Deck and then shuffle it. Draw the same number of cards that were in your hand from the Deck. (You cannot activate this card if you have your opponent's card in your hand.)" So, you choose one of your monsters on the field. Then you shuffle that monster, and all the cards in your hand, into your deck. Then you draw as many cards as you had in your hand previously, so if you shuffled three cards in, then you draw 3 card (note the monster you shuffled in does not count towards this). If somehow you have an opponent's card in hand, through Amazoness Chain Master or Exchange, then Monster Recovery cannot be activated.
No, it doesn't. The 40-60 limitation is for your main deck only.
No. If a card effect would cause a Synchro Monster to be returned to the Deck or the hand, it is placed back in the Extra Deck instead.
You cannot return fusion monsters to the hand. Fusion and synchro monsters have to be returned to the extra deck.
If an effect tries to return a Fusion or Synchro monster back to hand or deck, they go to the Extra Deck instead.
A Yu-Gi-Oh! Deck can contain anywhere between 40 and 60 cards, however most professional players play with 40 cards, since they have a greater chance of drawing the card they need each turn, that could win them the game. Fusion Monsters and Synchro's do not count as your deck, they go in your Extra Deck, as they are now known in 5Ds. If you look on a 5Ds play mat it says Extra Deck, if you look on an original it says Fusion Deck. Fusion Material Monsters and Tuner Monsters however, DO count as your deck and they must be placed within your main deck. Ritual Cards must also be in your main deck, as they do not fall into the category that allows you to place them in your Extra Deck, no idea why since they can't be summoned without a Ritual Spell Card.
Destroyed or tributed Fusion Monsters go to the graveyard. They will return to the Extra Deck if something tries to return them to hand or deck.
Since August 2008, a legal Yu-Gi-Oh deck has 40 to 60 cards in the main deck. It is no longer legal to have an 80 card deck (cards in your Extra or Side Decks do not count towards your main deck size limit).
Ritual monsters, and the rituals for them are in your regular deck.
A teammate cannot use an extra deck tag during dueling. Each player holds their own extra deck and it is not possible to use another teammates for play.
The situation that you are describing, in the first place, cannot exist (a Fusion monster being in your hand). If a Fusion monster on the field is supposed to be "sent to the top of the owner's deck" or "returned to the owner's hand" by an effect it is instead returned to the Extra/ Fusion deck.
Yes. It is not returned to the hand, but it is "returned", so damage is dealt.
No. If a card says to 'search your Deck', or 'send a card from the top of your Deck', this means your main deck. If something tries to return a Fusion monster 'to deck' though, that will put it back in your Extra Deck. That doesn't mean Extra Deck is the considered the same thing, that's just where Fusions and Synchros go when something tries to put them back in Deck.