@suzukaze -- you'd asked in an {{attention}} flag whether 沈菜 might be an alternative form. I find no conclusive evidence of this in use in Japanese (more below). However, it is included in the w:ja:キムチ article as the likely etymon for the Korean term -- see w:ja:キムチ#名称・表記 section.
FWIW, google books:"沈菜は" does generate 12 ostensible hits, collapsing to 11 when paging through. However, the first hit, while valid, is only a mention, and the others all appear to be scannos. Widening the search to the whole web, google:"沈菜は" generates 162 ostensible hits, collapsing to 43. Many of these are definitely only mentions of the form "the term "沈菜" is Korean for kimchi...". Some are proper nouns, like the name of this company in Aichi Prefecture. Others might demonstrate enough actual use to just barely meet CFI, if we can find this term in CFI-worthy materials, used in running text, and without a preceding explanation.
For now, I'd suggest we not include this as an alternative form. ‑‑ Eiríkr Útlendi │Tala við mig 23:47, 11 December 2017 (UTC)