Rulings
Q1: Does this card's digivolution requirement where it can digivolve from a Tamer mean that the Tamer that will become a digivolution card is treated as a Digimon when it digivolves?
No, it digivolves from the Tamer as-is.
Q2: When a Tamer would digivolve using this card's digivolution requirement, is it considered a Digimon that would digivolve?
No, it isn't considered a Digimon that would digivolve. When a Tamer would digivolve using this card's digivolution requirement, "when a Digimon would digivolve" effects don't trigger.
Q3: When a Tamer digivolves using this card's digivolution requirement, is it considered a Digimon that digivolves?
No, it isn't considered a Digimon that digivolves. When a Tamer digivolves using this card's digivolution requirement, "when a Digimon digivolves" effects don't trigger.
Data Sources
Lv.4 MetalKabuterimon BT18-067 R Hybrid | Variable | Cyborg [Digivolve] [J.P. Shibayama]: Cost 3/[Beetlemon]: Cost 1 <Blocker> [On Play] [When Digivolving] <De-Digivolve 1> 1 of your opponent's Digimon. --- Inherited: <Blocker> (This Digimon can block in the blocker timing.)
Lv.4 MetalKabuterimon BT18-067 R Hybrid | Variable | Cyborg [Digivolve] [J.P. Shibayama]: Cost 3/[Beetlemon]: Cost 1 <Blocker> [On Play] [When Digivolving] <De-Digivolve 1> 1 of your opponent's Digimon. --- Inherited: <Blocker> (This Digimon can block in the blocker timing.)
Lv.4 MetalKabuterimon BT18-067 R Hybrid | Variable | Cyborg [Digivolve] [J.P. Shibayama]: Cost 3/[Beetlemon]: Cost 1 <Blocker> [On Play] [When Digivolving] <De-Digivolve 1> 1 of your opponent's Digimon. --- Inherited: <Blocker> (At blocker timing, by suspending this Digimon, it becomes the attack target.)
Lv.4 ボルグモン BT18-067 R ハイブリッド体 | ヴァリアブル種 | サイボーグ型 「柴山純平」:コスト3/「ブリッツモン」: コスト1 ≪ブロッカー≫ 【登場時】【進化時】相手のデジモン1体を≪退化1≫。 --- Inherited: ≪ブロッカー≫（このデジモンはブロックタイミングでブロックできる）