Sort of: https://fed.brid.gy/
If you follow @bsky.brid.gy then your toots will also appear on BlueSky, but truncated if they're longer than 300 characters (I do this). BlueSky users will then be able to follow your Mastodon account, but you won't be able to see interactions from BlueSky users unless they also bridge their accounts.
From the other direction, if your BlueSky account follows https://bsky.app/profile/ap.brid.gy your BlueSky posts will appear in the Fediverse
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All GNU social JP content and data are available under the Creative Commons Attribution 3.0 license.