The Japanese version has different captions and descriptions. Here is the translated:
Cyborg Ninja If Snake is going to be a guest fighter, isn’t it good to have people from that world as assist figures?
Cyborg Ninja appears!
[Pic 1]
Oh. Cool mono-eye.
He comes in stealthily with light aerial jumps, then comes in to repeatedly slice. Ah, it makes you want to use him as a player character…
[Pic 2]
“Take my existing true feelings!”
By the way, he reflects projectiles.
[Pic 3]
“I surpass such weapons.”
When he appears, he speaks a little. If Snake is there, his speech content changes a bit?
[Pic 4]
“Dear old Snake.”
Oh, these assist figures can properly talk depending on the characters. Cyborg Ninja, with these single words, is also worthy of things like strong emotion, huh?