If they are hit with a move that uses ki damage, they will first regenerate ki. Then when the Ki bar is full, they will start to gain health equal to the amount of Ki damage received, including melee moves that use the Ki stat to determine damage (Power Impact, Double Launcher, etc).
Moves that will not regenerate Ki or Health include HBTC Goku's Warp Kamehameha and Kamehameha.
They will be "guard-broken" (though not removed from Energy Absorption) once hit with a basic melee attack or any other melee based move.
They will be unable to auto regenerate Ki while Energy Absorption is active.
Can block any auto-combo move.
Advantages Against Other Races
If the two Androids were melee builds, either one may gain the upper hand, but may face difficulty with Ki Max.
Although Frieza Races, which are purely ki-based, can use quick ki moves such as Power Impact and Emperor's Edge, Androids would still be able to use Energy Absorption to handle it.
Human transformations arguably have the largest ki drainage, while Androids don't have any ki drainage at all.
Unstable Majins can auto-vanish, similar to Ultra Instinct, making them unpredictable and difficult to hit.
Namekians outmatch Androids by their dramatic Ki Max difference. Especially in long fights, in terms of Ki Max, Namekians will be able to endure well against Androids, because of their hidden Ki Max buffs, while Androids on the other hand may face trouble.
Since Saiyans depend on transformations with large ki drains, Androids, having no ki drain, can (although not that easily) gain the upper hand.
These predictions are what is most-likely to happen, and are not extremely accurate.
These predictions are based on what would happen if this race fought another in PvE, not PvP.
Due to the lack of transformations, Androids will always remain in base form and receive the full reward for defeating NPCs by proxy.
If an Android fuses with a player of another race, the Fusion can't charge or regenerate Ki due to the form's drain, and Energy Absorption doesn't work. The only way to regain Ki is for the non-Android player to gain control and charge.
If an Android player uses Babidi's Magic, they will be unable to regenerate Ki, until the Majin gamepass is turned off.
Androids benefit the most from red jars/beans, due to them multiplying the player's base damage stats (melee damage and Ki damage) which Androids have the highest of.
Androids also benefit the most from Prestige due to Androids having the highest base stat, meaning they pass down more stats than other races.
Many non-Android players have a grudge towards the Androids, deeming them "overpowered" or simply “annoying”.
"Hybrids" are no longer obtainable (getting a high level Android, then using the Dragon Balls to become a Saiyan and keeping the base stats while being able to transform).
The way an Android poses to activate Energy Absorption might've been based off on Android 19's way of absorbing ki.
"Android" is not the official name for the race. In the original (Japanese) dub of Dragon Ball Z, the race's name can be translated to "Artificial Human" (Jinzōningen).
Differences between Androids in the anime/manga and the game include:
In the anime/manga, Androids' ki cannot be detected, nor their power level, since they are artificial. However, in the game, their ki and power level can be sensed like other races.
Androids can fly without ki usage in the anime/manga. It's the opposite in the game.
It is implied in the anime/manga that Energy Absorption not only regains health and ki, but also strengthens them. However, this type of power-up not happen in the game.
It is implied in the anime/manga that Androids can extract life energy from grabbing a life form, as evidenced by Android 20 (Dr. Gero) absorbing Yamcha's energy by holding him in a choke-hold, and Android 19 draining Goku's energy by holding him down. This technique doesn't exist in the game.