Neither of those substances is listed specifically as a controlled substance in Florida. Because of this, many people think that substances like these are "legal." However, both Florida and the U.S. have passed laws that also outlaw "analog" drugs... that is a chemical that is intended to do the same thing as a chemical on the controlled substance schedules.
Generally, "analogs" are only illegal if they are intended to substitute for schedule I or Schedule II drugs (the more addictive and severe kinds). This is why sometimes things like K2 are not illegal, because they are intended to mimic marijuana which is a schedule IV.
Specifically, in this case, methiopropamine is a substitute for methamphetimine, and would thus be an analog of a schedule I drug, making it the same crime as possessing meth (if intended for ingestion).
Methoxetamine is an analog for ketamine, which is schedule III in the U.S. but I believe schedule II in Florida. Even if it is not scheduled, you could still be prosecuted if they can show it was used as an analog to a schedule II drug.
BotXXXXX XXXXXne, methiopropamine is definitely illegal. Methoxetimine is probably illegal, but there is a little more gray involved. Again, this is going to vary depending on how it is charged, and you could definitely be prosecuted for it, the same as possessing any other scheduled substance.
See the law here: http://www.flsenate.gov/Laws/Statutes/2011/893.0356