Hi Qazik,
The developers confirmed that there are no similar commands.
You can indirectly increase the delay time of the routes by changing the reconnection timer for the feasts. Please refer to https://support.huawei.com/hedex/hdx.do?docid=EDOC1100053999&id=EN-US_CLIREF_0141119727&lang=en
In this case, the delay in setting the neighbor BGP will cause the delay in advertising the routes.
I hope it helps!