WeWork’s board is expected to meet Tuesday to weigh emergency-financing options including a takeover by SoftBank Group Corp. that would slash the co-working company’s valuation to about $8 billion and alleviate a looming cash crunch.

Ahead of a Monday deadline to submit bids, SoftBank has offered to lend $5 billion to the struggling startup and accelerate a $1.5 billion equity investment that had been scheduled for next year, people familiar with the matter said. SoftBank also would offer to buy more than $1 billion of stock...