You have seen redaction tools that merely draw a box over the data, with the original recoverable underneath, and you want to know whether Omni is different.
It is different on purpose. Redaction in Omni is destructive: pixelation is baked into the exported pixels rather than overlaid, so redacted data cannot be recovered from a saved, exported, or shared file. What you redact stays redacted.
Redact in the capture editor before copying, downloading, or sharing, and the exported image genuinely no longer contains the data. There is no recovery after export, which is the point, so check the region before you save.