Thank you to everyone that has reached out with more data. Made a couple corrections in the OP. Archiving the starting tables here since old sales are going to be constantly replaced - i.imgur.com/HiA30A7.png & i.imgur.com/GwkVkwd.png
In terms of general price trending, most cards seem to have peaked and are now coming back to earth a bit.
Since the sales are so few and far between for these in general, I think I can keep up with pretty much every graded sale in here so… Dumping some extra data to start to try to fill in the gaps and plot some history since the table only shows last sold. Sales are from the last few months unless otherwise stated.
Treecko
UED PSA 8 - 575
Torchic
1ED PSA 7 - 460
1ED PSA 10 - 3250
Mudkip
1ED CGC 8.5 - 1250
UED PSA 9 - 900
Latias
1ED PSA 5 - 200
1ED PSA 8 - 490
1ED BGS 9 - 825
UED PSA 8 - 440
UED CGC 8.5 - 460
UED PSA 10 - 4050
Latios
UED PSA 10 - 3050
Rayquaza
1ED PSA 5 - 1600
1ED PSA 8 - 2200
1ED PSA 8 - 1550
1ED CGC 6 - 2000
1ED PSA 10 - 15300
1ED PSA 10 - 9500 (unpaid)
1ED BGS 9.5++ - 9350
UED CGC 6.5 - 1700
Entei
UED PSA 7 - 230
UED PSA 10 - 1925
1ED PSA 10 - 1488
Raikou
UED PSA 9 - 625
Suicune
UED PSA 7 - 260
Groudon
UED PSA 5 - 170
1ED BGS 9 - 390
1ED PSA 10 - 1300
1ED PSA 10 - 1470
KyogreUED PSA 5 - 160
Metagross
1ED PSA 10 - 2850
1ED PSA 10 - 2000
1ED PSA 10 - 1625
Regice
1ED PSA 10 - 1000 EUR
Regirock
Registeel
1ED PSA 10 - 1280
CelebiPSA 8 - 550
Alakazam1ED PSA 10 - 1175
1ED PSA 10 - 1225
1ED PSA 10 - 1305
Gyarados
1ED CGC quad 9.5 - 1250
1ED CGC 9.5 - 1000
1ED CGC 9 - 725
1ED PSA 9 - 1227
1ED PSA 10 - 900 GBP
1ED PSA 10 - 1530
1ED BGS 9.5 - 860
Charizard
UED PSA 8 - 1050
1ED PSA 7 - 1010
1ED PSA 8 - 1475
1ED PSA 10 - 8600
1ED PSA 10 - 4682
Mew
UED BGS 9.5 - 1950
Mewtwo
PSA 8 - 375
PSA 8 - 425
CGC 8.5 - 260 GBP
PSA 9 - 430
PSA 10 - 1025
PSA 10 - 1050
PSA 10 - 1400
Pikachu
PSA 8 - 365
PSA 8 - 380
PSA 9 - 653
PSA 10 - 1625
PSA 10 - 1800
PSA 10 - 132,000 JPY
Vaporeon
PLAY PSA 10 - 3175
1ED WCP PSA 7 - 395
PLAY PSA 8 - 760
Jolteon
1ED WCP PSA 8 - 270
PLAY BGS Black Label - 20000
PLAY BGS 9.5 - 1600
Flareon
PLAY sealed - 498,000 JPY
Espeon
Sealed - ~1,900,000 JPY (graded PSA 9)
Umbreon
PSA 6 - trade for Master’s Key PSA 9
BGS 9.5 - 70000