FRANKFURT—Commerzbank Chief Executive Manfred Knof on Feb. 3 finalized plans to cut 10,000 jobs and close hundreds of branches, a radical overhaul that came a month after he took the reins of Germany’s No. 2 bank. The bank also announced that it would post a net loss of nearly 2.9 billion euros ($3.5 billion) for 2020, compared with a profit of 585 million euros a year earlier. The bank’s management team hopes the revamp will revive the fortunes of the partly state-owned lender, which has struggled to boost profits amid executive reshuffles and strategy zig-zags. The bank has never fully recovered after a state bailout during the last financial crisis more than a decade ago. Knof made public the plan’s outline two weeks ago but was still discussing details with the supervisory board and management over the next days. He has argued that the cuts were a necessary “bitter pill,” …