Rolling Over 401k with Negative Rate of Return

I left company A about 8 months ago and did not rollover my 401k into the 401k for company B. I continue to pay the quarterly fees. I would like to rollover my 401k into company B to avoid paying fees for both 401ks and to simplify the accounts.

I noticed that I have a negative rate of return in company A’s 401k (cost basis greater than current value). Would this cause problems when rolling over to another 401k? Will the company B 401k account for the previous cost basis?

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Note: This is for Traditional 401k, and I cannot rollover into IRA because I have done backdoor IRA conversions.