Hey there, @Hammerfall. I can’t personally be of much help since I was never big on isometric mech shooters… although I do adore '90s games.
With that said, I sill have suggestions. Do you have a Reddit account? There’s a really handy subreddit for things like this called Tip of My Tongue – or TOMT, for short. Eventually, that led to the creation of Tip of My Joystick – you guessed it, same drill but for games! They might be able to lend you a hand there! Addionally, I recently found an answer to a story my father had been looking for for years on Stack Exchange, so maybe ask for help on the Arqade, their gaming section?
Not to say, by any means, that people on Chrono wouldn’t be able to help you. It’s just that those are bigger communities, so you might want to seek help wherever you can get it!
Just for kicks though, see if the answer you are looking for is in any of these places:
[PC][90’s-Mid 2000’s] Mech-based First Person Shooter
Correct answer: Cyberstrike 2
Looking for an old top down pc Mech game
Correct answer: Zulu Assault
[PC][EARLY 2000s/LATE 90s]Isometric Mech Shooter
Correct answer: None
Additionally, there are these two huge threads you can give a shot and post on:
a) Old Games you remember playing but can’t remember the name of. - The Escapist
b) The “Can’t remember the name of this game” Thread v3.0 - Giant Bomb
Whew! Hope this helps, in any way. Good luck. I’ll keep an eye out for this thread to be notified of when you find it.
Search engine used: DuckDuckGo
Queries: “90s top down mech shooter take over enemy mech”; “90s top down mech shooter DOS”.
Edit: I also found this.