The mapping is not strictly one index per field, but a virtual column expression must map to a MySQL type. So depending on the use-case you may be able to use more complicated expressions to limit indexes.
But to expand your question, there are two FRs we are looking at:
i believe you have to create a virtual column on specific document fields and create a secondary index on that similar to what you do with Postgres' expression indices, I do not think MySQL has a general JSON GIN index yet
The optimizer will match JSON expressions to virtual columns w/indexes. So that means you can keep your queries in this form and have them indexed:
EXPLAIN SELECT * FROM features WHERE feature->"$.properties.STREET" = 'MARKET'\G