Generally, no. Game mechanics only permit a player to Synchro Summon on their own turn. The only exception to this rule is the Urgent Tuning card which can be activated during your opponent's Battle Phase as well as your own .
Urgent Tuning
Attribute: TRAP
Property: Normal
Activate only during the Battle Phase. Synchro Summon 1 Synchro Monster. (Send the appropriate Synchro Material Monsters to the Graveyard.)
Now you can because since there was a new form of synchro summoning call accel synchro which allows you to summon one when it your opponents' turn at anytime on that turn but you must have the requirements on the field first before doing an accel synchro summon.
Yes, you can, as a Synchro Summon is a special summon, you can perform a Normal Summon on the same turn as one or more Synchro Summons.
No, you do not 'tribute' the Synchro Material for a Synchro Summon. They are sent to the graveyard, not tributed. You can tribute an opponents synchro monster for "Assault Mode Activate!" to summon the assault mode monster from your deck.
Yes, of course. You are allowed to perform as many special summons in a turn as you've got the resources to do so, Synchro and Fusion summons are kinds of special summon.
No, a Synchro Summon is a kind of Special Summon.
Not quite. A Synchro Summon is a Special Summon. A Tribute Summon is the same as a Normal Summon, except that when you Tribute Summon you need to tribute monsters. Also you can Special Summon as many times as you want to in a turn, whereas you can only Normal Summon OR Tribute Summon once per turn, except with a card effect.
Yes, you can, as a Synchro Summon is a special summon, you can perform a Normal Summon on the same turn as one or more Synchro Summons.
No, you do not 'tribute' the Synchro Material for a Synchro Summon. They are sent to the graveyard, not tributed. You can tribute an opponents synchro monster for "Assault Mode Activate!" to summon the assault mode monster from your deck.
Somewhat, yes. A synchro does not count for you Normal Summon for the turn. This means that you can do multiple Synchro summons in one turn. But if you are implying that a Synchro Summon can be usd for a card effect triggerd by or that needs a special summon, then a Synchro summon will not count. ^That's a bit vague. Synchro Summons will most certainly trigger/count towards effects that look for Special Summons - case in point, Bottomless Trap Hole, which can respond to a Synchro Summon because it is a kind of Special Summon. Special Summon is the default, and then you have special types, like Fusion Summon and Synchro Summon. Anything that looks for a Special Summon, will trigger from any of those. However if it only triggers from a Synchro Summon, then only a Synchro Summon will do, not a regular Special Summon.
Nope. Same as De-Fusion. You can't get an opponent's monster on your side of the field by activating De-Synchro or De-Fusion.
Yes, of course. You are allowed to perform as many special summons in a turn as you've got the resources to do so, Synchro and Fusion summons are kinds of special summon.
No, a Synchro Summon is a kind of Special Summon.
Not quite. A Synchro Summon is a Special Summon. A Tribute Summon is the same as a Normal Summon, except that when you Tribute Summon you need to tribute monsters. Also you can Special Summon as many times as you want to in a turn, whereas you can only Normal Summon OR Tribute Summon once per turn, except with a card effect.
Yes you can. You may perform as many Special Summons (Synchro Summons are Special Summons) in a turn as you have the resources to do so, as well as your one-per-turn Normal Summon/Set. You can do them in any order, either before or after your turn Normal Summon.
You can perform as many special summons in a turn as you have available resources to do so, there is no hard limit. Yes, you can use Rescue Cat to summon a Tuner and another monster, and then use them in a Synchro Summon - the turn has a restriction on normal summons, but not Special Summons. (Also note, you do not 'tribute' the components for a Synchro Summon, you just send them to the graveyard.)
Yes you can, as long as the Stardust was originally summoned by Synchro Summon and not by Starlight Road (Starlight Road does not summon it 'properly', and the Stardust Dragon summoned by it cannot be summoned back from the graveyard should it be sent there).
You can only do so if a card effect specifically lets you, like Call of the Haunted. Otherwise, regular Special Summons, Synchro, Fusions, XYZ's, etc, all must be done on your turn in your own main phases.
Yes, Tokens have a level and can be used in a Synchro Summon.