All are Japanese, except as specified. 
Some (Box), (Limited Edition) or (First Press) should be dupe, but, we rather like to verify this fact.

Anchorz Field
Another Heaven ~Memory of Those Days~
Bakusou Dekatora Densetsu for WonderSwan
Beat Mania for WonderSwan
Blue Wing Blitz
Buffers Evolution
Card Captor Sakura   Sakura to Fushigi na Clow Card
Chocobo no Fushigi na Dungeon for WonderSwan (Box)
Chou Denki Card Battle   Youfu Makai   Kikuchi Shuugou
Chou Jiku Yousai Macross -True Love Song-
Crazy Climber
D's Garage21 Koubo Game   Tane wo Maku Tori
Dark Eyes ~Battle Gate~
Densha de Go !
Densha de Go ! 2
Digimon Adventure Anode Tamer (Box)
Digimon Adventure   Cathode Tamer
DigiMon Ver. WonderSwan (English Version)
DigitalMonster Ver. WonderSwan
Digital Partner
Digital Partner   WonderWave Edition
Dokodemo Hamster for WonderSwan
Dokodemo Hamster 3   O Dekake Saffron
Fever for WonderSwan   Koushiki Pachinko Simulation
Final Fantasy (Box)
Final Lap 2000
Final Fantasy II
Final Fantasy II (Limited Edition)
Fire Pro Wrestling For WonderSwan
Fishing Freaks Bass Rice for WonderSwan
Flash Koibito Kun
Ganso Jajamaru Kun
Global Hexcite
Goraku  Tango !
Guilty Gear Petit
Gunpey Ex
Hanafuda Shiyou Yo
Harobots
Hataraku Chocobo
Hunter X Hunter ~Ishi wo Tsugu Mono~
Hunter X Hunter ~Sorezore no Ketsui~
Itou Junji Uzumaki   Noroi Simulation
Kakutou Ryouri Densetsu Bistro Recipe ~Wonder Battle Hen~
Kaze no Klonoa ~Moonlight Museum~
Keiba Yosou Shien Soft   Yosou Shinkaron
Kiss Yori... ~Seaside serenade~
Kyousou Uma Ikusei Simulation   Keiba
Langrisser Millenium WS  The Last Century
Last Alive
LastStand
Lime Rider Kerorikan
Lode Runner for Wonder Swan
Magical Drop for WonderSwan
Mjan Touryuumon
Makai Mura for WonderSwan
Medarot Perfect Edition (Kabuto Version)
Medarot Perfect Edition (Kuwagata Version)
Meitantei Conan   Majutsushi no Chousenjou !
Meitantei Conan   Nishi no Meitantei   Saidai no Kiki !?
Meitantei Conan   Yuugure no Koujo
Memories of Festa
Metha Communication Therapy   Ne Kiite !
Moero !! Pro Yakyuu Rookies
Mikeneko Home's Ghost Panic
Mingle Magnet
Mobile Suit Gundam MSVS (Box - Zeon Color)
Mobile Suit Gundam MSVS (Box - Earth Federation Color)
Morita Shogi for WonderSwan
Mr. Driller
Nice On
-chan no O Ekaki Logic
Pocket no Naka no Doraemon
Pro Mjan Kiwame for WonderSwan
Rainbow Islands   Putty's Party
Raku Jongg
Rekishi Simulation Sangokushi II for WonderSwan
Ring Infinity (First Press)
Sangokushi for WonderSwan
SD Gundam Eiyuuden ~Kishi Densetsu~
SD Gundam Eiyuuden ~Musha Densetsu~
SD Gundam G Generation Gather Beat (WonderWave Box)
SD Gundam G Generation   Gather Beat 2
SD Gundam Gashapon Senki   Episode 1
Senkaiden ~TV Animation Senkaiden Houshin Engi~
Sennou Millenium
Shanghai Pocket
Shin Nihon Pro Wrestling Toukon Retsuden
Shin Seiki Evangelion Shi to Ikusei
Shinchou no Yabou for WonderSwan
Shisodate Quiz Dokodemo My Angel
Shougi   Touryuumon
Sleezer Link
Soccer Yarou ! ~Challenge the World~
Sotsugyou for WonderSwan
Space Invaders
Super Robot Taisen Compact
Super Robot Taisen Compact 2   Dai Ichibu   Chijou Gekidou Hen
Super Robot Taisen Compact 2   Dai Sanbu   Ginga Kessen Hen
Taikyoku Igo   Heisei Kiin
Tanjou ~Debut~ for WonderSwan
Tare Panda no Gunpey
Tare Panda no Gunpey (Box)
Terrors (First Press)
Terrors 2
Tetsuman
Time Bokan Series   Bokan Densetsu   Buta Mo O Daterya Doronbou
Toukyou Majin Gakuen Fuju Fuuroku
Trump Collection   Bottom Up Teki Trump Seikatsu
Trump Collection 2 Bottom Up Teki Sekai Isshuu no ??
Turntablist   DJ Battle
Uchuu Senkan Yamato
Umizuri ni Ikou !
Uzumaki ~Denshi Kaiki Hen~
Vaitz Blade
Wasabi Produce   Street Dancer
Wild Card
With You ~Mitsumete Itai~
With You ~Mitsumete Itai~ (First Press)
Wizardry   Scenario 1 Kyounou no Shiren Jou
WonderSwan Handy Sonar
Wonder Classic
Wonder Stadium
Wonder Stadium '99