[@DarkRecon]: Hm...

Well, there's... A lot to unpack here, but I'll go down one by one.

[list][*]Minor point: Infection by standard means (read: mouth) guarantees mutation. Can't have that.
[*]The character as a whole seems very... How do I put this... Flat? Amnesia plus lone wolf plus no connections to people means that the character has no stake in... Well, pretty much anything, as far as I can tell. That's probably the biggest problem that I have here; from getting dragged along by the government into being sent off for a 'goodwill' program (which is also something I'll get to), the dude has next to no reason to interact with other characters and thus in my opinion wouldn't mesh well with the rest of the cast.
[*]The reason that people are scouted is [i]because[/i] they haven't been picked up yet locally; national security is very important to pretty much every city-state/nation in the current state of the world, and so giving up perfectly usable personnel to an international organization (even if they do provide aid) does not seem like something that would happen in the first place—doubly so given that they are essentially a PMC in the grander scheme of things. I also believe that such an offer would likely be rejected out-of-hand given the timeline and circumstances anyways; Chi-Mechframes are [i]expensive[/i] and gearing temporary personnel comes at a loss, and sending staff [i]with[/i] said equipment carries a very heavy financial burden on the party offering with a very real risk of no return. Presenting an 'offering of goodwill' to an independent organization with high risk and comparatively low return does not sit well with me, and I doubt that it would with any high-ranking officials in-universe.
[*]Minor point two: given that he is an amnesiac that was found in an abandoned apartment, how would he even have any material possessions? There wouldn't be anyone to confirm if they were his or not on-location, and given that search-and-rescue was the means by which he was found, anything not explicitly important to him (e.g. any form of ID, which given the circumstances of his name he would not have had on his person) would likely not have been retrieved.
[*]The walking contradiction that is the despondence of the character towards any intent of pressing forward in spite of the circumstances and the presence of a strong will is also... Odd? As it stands, they come off as wholly resigned to their fate and only continue to push through because of a combination of what momentum they have and people around them more or less forcing him ahead. Things just don't line up on that front.[/list]

Hmmm... Yeah, that's about it for my thoughts on the matter at the moment. As for equipment design... I'd probably prefer something more akin to, say, tokusatsu outfits than smaller mecha to fit with the current cast aesthetic, but that part is less mandatory than what's been stated thus far.