Q1: If the cards I reveal from my deck for this card's effect include only either Kiriha Aonuma or 1 blue or black card with DigiXros requirements, can I only add 1 card to my hand?
Yes, even if you only reveal one of the applicable cards, you can still add it to your hand.
Q2: If the cards I reveal from my deck for this card's effect include both Kiriha Aonuma and 1 blue or black card with DigiXros requirements, can I add 1 card to my hand and trash the rest?
No. If you have cards that are targets of this effect, you must add as many cards to your hand as possible.
Lv.4 Greymon EX4-016 U Champion | Virus | Dinosaur/Blue Flare [On Play] Reveal the top 3 cards of your deck. Add 1 [Kiriha Aonuma] and 1 blue or black card with DigiXros requirements among them to your hand. Trash the rest. [On Deletion] <Save> (You may place this card under one of your Tamers.) --- Inherited: [When Attacking] <Draw 1>. (Draw 1 card from your deck.)
Lv.4 Greymon EX4-016 U Champion | Virus | Dinosaur/Blue Flare [On Play] Reveal the top 3 cards of your deck. Add 1 [Kiriha Aonuma] and 1 blue or black card with DigiXros requirements among them to your hand. Trash the rest. [On Deletion] <Save> (You may place this card under one of your Tamers.) --- Inherited: [When Attacking] <Draw 1>. (Draw 1 card from your deck.)
Lv.4 Greymon EX4-016 U champion | Virus | Dinosaur/Blue Flare [On Play] Reveal the top 3 cards of your deck. Add 1 [Kiriha Aonuma] and 1 blue or black card with DigiXros requirements among them to your hand. Trash the rest. [On Deletion] <Save>. --- Inherited: [When Attacking] <Draw 1>.
Lv.4 グレイモン EX4-016 U 成熟期 | ウィルス種 | 恐竜型/ブルーフレア 【登場時】自分のデッキの上から3枚オープンする。その中の「蒼沼キリハ」と青か黒のデジクロス条件を持つカード1枚ずつを手札に加える。残りは破棄する。 【消滅時】≪セーブ≫(このカードを自分のテイマーの下に置ける) --- Inherited: 【アタック時】≪1ドロー≫(自分のデッキからカードを1枚引く)。