Rulings
Q1: Can I use this card's On Play When Digivolving effect to give "End of Attack Delete this Digimon" to a Digimon that isn't affected by effects?
You can give that effect to such Digimon, but Digimon that aren't affected by effects won't be affected by it. Therefore, after an attack ends for a Digimon that isn't affected by effects, "End of Attack Delete this Digimon" won't trigger.
Q2: Can I use this card's On Play When Digivolving effect to give "End of Attack Delete this Digimon" to a Digimon, then it's deleted, does <Partition> on that Digimon trigger?
No, it doesn't trigger. If this card's On Play When Digivolving effect gives "End of Attack Delete this Digimon" to a Digimon, then it triggers, that Digimon's player will be the player considered to have triggered/activated that effect, therefore <Partition> won't trigger.
Data Sources
Lv.5 LadyDevimon (X Antibody) EX7-058 R Ultimate | Virus | Fallen Angel/X Antibody [Digivolve] [LadyDevimon]: Cost 0 [On Play] [When Digivolving] Until the end of your opponent's turn, give 1 of their Digimon "[End of Attack] Delete this Digimon." Then, if [LadyDevimon] or [X Antibody] is in this Digimon's digivolution cards, you may play 1 [Volée & Zerdrücken] Token. (Digimon/Lv. 4/Purple/5000 DP/<Blocker><Retaliation>) --- Inherited: [Opponent's Turn] [Once Per Turn] When any of your opponent's Digimon are deleted, you may play 1 level 4 or lower purple Digimon card from your trash without paying the cost.
Lv.5 LadyDevimon (X Antibody) EX7-058 R Ultimate | Virus | Fallen Angel/X Antibody [Digivolve] [LadyDevimon]: Cost 0 [On Play] [When Digivolving] Until the end of your opponent's turn, give 1 of their Digimon "[End of Attack] Delete this Digimon." Then, if [LadyDevimon] or [X Antibody] is in this Digimon's digivolution cards, you may play 1 [Volée & Zerdrücken] Token. (Digimon/Lv. 4/Purple/5000 DP/<Blocker><Retaliation>) --- Inherited: [Opponent's Turn] [Once Per Turn] When any of your opponent's Digimon are deleted, you may play 1 level 4 or lower purple Digimon card from your trash without paying the cost.
Lv.5 LadyDevimon (X Antibody) EX7-058 R Ultimate | Virus | Fallen Angel [Digivolve] [LadyDevimon]: Cost 0 [On Play] [When Digivolving] 1 of your opponent's Digimon gains "[End of Attack] Delete this Digimon." until the end of their turn. Then, if this Digimon has [LadyDevimon] or [X Antibody] in its digivolution cards, you may play 1 [Volée & Zerdrücken] Token (Digimon/Lv.4/Purple/5000 DP/<Blocker>/<Retaliation>). --- Inherited: [Opponent's Turn] [Once Per Turn] When an opponent's Digimon is deleted, you may play 1 purple level 4 or lower Digimon card from your trash without paying the cost.
Lv.5 レディーデビモンX抗体 EX7-058 R 完全体 | ウィルス種 | 堕天使型/X抗体 「レディーデビモン」:コスト0 【登場時】【進化時】相手のターン終了まで、相手のデジモン1体に「【アタック終了時】このデジモンを消滅させる。」の効果を与える。その後、このデジモンの進化元に「レディーデビモン」/「X抗体」があるなら、「ヴォーレ＆ツェードルゥケン」（デジモン• Lv.4• 紫• DP5000• ≪ブロッカー≫≪道連れ≫）トークン1体を登場できる。 --- Inherited: 【相手のターン】[ターンに1回]相手のデジモンが消滅したとき、自分のトラッシュから、紫のLv.4以下のデジモンカード1枚をコストを支払わずに登場できる。