To correct the hypothetical, it wouldn't be Biden restoring Obama-era regulations through executive orders, but rather government agencies doing so through the rulemaking process of promulgating regulations.
In any event, though: no, the government agencies wouldn't be able to restore such regulations unless explicitly authorized to do so by Congress because, once pending regulatory rules are repealed by Congress under the purview the Congressional Review Act, government agencies are prohibited from reissuing such rules in substantially the same form or from issuing new rules that are substantially similar "unless the reissued or new rule is specifically authorized by a law enacted after the date of the joint resolution disapproving the original rule," per
5 U.S. Code § 801(b)(2).