I work as a SEO consultant. I have been doing so for several years, however this is the first year my partner has decided to opt out and left everything to me.

all is fine and well, but since I am located in Mexico, and for personal reasons my tax state is on hold or suspended, if you may. Now, as a Mexican tax person, any invoices I issue will be of no use to USA business men and women. So, in this case, I would really like to know, is there any other way they can deduct my services?

I mean, if it were Mexico, I would tell them to increase their consumables amount and deduct the service through that area, as it is not over $4k at the time.

Another idea I would tell them is to get varieties purchases or deduct them as "miscellaneous"...

Is that also doable in the USA?

Mexican TAX laws are quite friendly if you happen to be smart enough to read through the tax law books.