These games do not save the wonder card in their saves, however some details are left behind, in the form of the Wonder Card Records Album (or Gift Records Album).
Findings may be incomplete, until more events gets released.
Starts at 0x45600, taking up every 0x140
0x45600 to 0x45604
0x000 to 0x004
Epoch Time code of Event received
0x45608 to 0x45609
0x008 to 0x009
Wonder Card ID
Wonder Card Type (as listed below)
0x01 are for Pokémon type
and 0x02 are for Item type.
Number of kinds of Items, max 06 (for Item-Type gift only)
0x4570C to 0x4570D
0x00C to 0x00D
Species Value for Pokémon
Item ID 1 for Items only
0x4570E to 0x4570F
0x10E to 0x10F
Amount of Item ID 1, for Item-Type gift only
0x45710 to 0x45724
0x110 to 0x124
Item IDs and Amounts
(2 byte of Item ID, 2 byte for amount, repeat)
0x45710 to 0x45711
0x110 to 0x111
Move 1 ID, for Pokémon-Type Gift.
0x45714 to 0x45715
0x114 to 0x115
Move 2 ID, for Pokémon-Type Gift.
0x45718 to 0x45719
0x118 to 0x119
Move 3 ID, for Pokémon-Type Gift.
0x4571C to 0x4571D
0x11C to 0x11D
Move 4 ID, for Pokémon-Type Gift.
0x45720 to 0x45739
0x120 to 0x139
Original Trainer (used for Pokémon-Type Gift)
(follows trainer name if it's unset)
Presumably end marker for OT name Potentially Multiples-Redeemability indicator
Probably language tag assigned upon being received.
02 on Mewtwo and Mew (was redeemed on ENG)
01 on Chansey (forced set to JPN)
Wonder Card Type
[VAR PKNAME(0000)] Gift
[VAR ITEM2(0008)] Gift
Item Set Gift
[VAR 0104(0001)] [VAR PKNAME(0000)] Gift
Mythical Pokémon [VAR PKNAME(0000)] Gift
[VAR TRNAME(0003)]’s [VAR PKNAME(0000)] Gift
Shiny [VAR PKNAME(0000)] Gift
[VAR PKNAME(0000)] ([VAR 01CA(0002)]) Gift
[VAR 01CA(0002)] Gift
Hidden Ability [VAR PKNAME(0000)] Gift
[VAR MOVE(0004)] [VAR PKNAME(0000)] Gift
[VAR PKNAME(0000)] with [VAR MOVE(0005)] Gift
[VAR PKNAME(0000)] with [VAR MOVE(0006)] Gift
[VAR PKNAME(0000)] with [VAR MOVE(0007)] Gift
[VAR PKNAME(0000)] & [VAR ITEM2(0009)] Gift
Downloadable Version Bonus
Special Pack Purchase Bonus
Store Purchase Bonus
Strategy Guide Purchase Bonus
Virtual Console Bonus
Pokémon Trainer Club Gift
Pokémon Global Link Gift
Pokémon Bank Gift
Can't get WC type 14 to function properly. Keep getting "Mew & None Gift" (Mew intended, None unintended). When I swap past an item entry, the None get's updated to the third item.
Maybe this type is a remnant of Gen 8's system?
WC type 10 seems to work as per normal, however can't get WC type 11 to 13 to function, even after various tests.
I have concluded that it is possibly leftover/unused, as those 3 entries were phrased different from WC type 10, on top of the "not working" issue. Either that, or there's a byte that controls the amount of moves a Pokemon has, and I'm clearly missing it., and so are the other 3!
Big thanks to @wo0ts for the various contributions for gift records!