Hi Andre, these may sound simple but I thought I’d chime in anyway if this helps:
a) in the Field Settings for each field, you can modify the Placeholder and the Custom Validation Message to be whatever language you want (enter/paste your text).
b) I’m not sure the above would help with the “Required” notice, but this would: you can use the WP Settings > General > Site Language to turn the entire user-facing website language into Spanish. The Admin back-end can be in English or whatever language selected for that particular Admin user login via Users > Profile [admin username]… there’s a Language selector. Each admin can have their WP backend in a different language of their choice.
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