Correct spelling for the English word "Porchusa" is [pˈɔːt͡ʃuːsə], [pˈɔːtʃuːsə], [p_ˈɔː_tʃ_uː_s_ə] (IPA phonetic alphabet).
There doesn't seem to be any widely recognized etymology for the word "Porchusa". It is not listed in any dictionaries or scholarly sources, and there are no distinct linguistic elements that can be analyzed to trace its origin. It is possible that "Porchusa" is a proper noun or a term specific to a particular region, group, or context, making its etymology difficult to determine without more information.