From the official Twitter account.

Atlur Kabuterimon

Card NumberBT1-076Level5
Card TypeDigimonPlay Cost7
ColorGreenEvolution Cost2
Digimon TypeInsectDP6000
AttributeVaccineRarityUncomon
StagePerfectArtist Nakano Haito
Main Effect
Source Effect[When it attacks] If your opponent has 2 or more Rested Digimon, +1 Memory.

Testament

Card NumberBT1-103Level
Card TypeOptionPlay Cost3
ColorYellowEvolution Cost
Digimon TypeDP
AttributeRarityRare
StageArtistMATSUMOTO EIGHT
Main Effect[Main] Until the end of your opponent’s next turn, 1 of your Digimon gets <<Blocker>>. (When your opponent’s Digimon attacks, you may Rest this Active Digimon to make it the target of that attack.)
Security Effect[Security] <<1 Draw>> (Draw 1 card from your deck.) Then, add this card to your hand.

Booster 1 launches in Japan on May 15th, 2020.