They should tell you if they use it or not, except they dont. Look at this lovely example of a 072 Project(now known as 072 Project X on steam for some reason)
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That was taken from the Official MTL of "MAOUISHO:~ La Dolce Vita with Another World's Demon Lord" . Not to mention the mess Crypt Render is, so bad that even the old saikey mtl is better than it.
So unless a game is being localized by Kagura games or Shiravune , you will be paying for a localization ran trough chatgpt without any edits.
At this point bokiboki , 072Project and Hanabi Games are trying to compete for "who uses the most mtl possible to bait western buyers, Paradise Project style". (and yes all of those 3, 100% use mtls, at least for the western audience).
Otakuplan haz its ups and down because sometimes they do actual legit localizations.
Its honestly very easy to know when a mtl was used as a localization. Regardless people will still buy those MTLs which pretty much telling those companies "go ahead and release some more unedited/bad mtls". And said companies will never admit nor disclaim that they use MTLs