Which word can't you find a suitable translation for in the dictionary? They're all listed.

I am not sure, which one of the listed words fits most perfect.
I think, that 'In consideration of the waiting time' will do best,
but 'Having regard to the waiting time' sounds also good for me.

Do native speakers use both in the way I need them, or is one way better than the other?

'in consideration of' and 'having regard to' both sound very formal and are the sort of phrases that IMHO you are most likely to find in contracts or official reports written by civil servants.

I would suggest that what you want here is 'taking into account'.

Thank you very much, that's what I needed

Considering the usual waiting period this is (would be) the latest possible date.

Oder, RRRobin folgend:

Taking into account the usual waiting period this ...

This is a phrasal verb. I know this, because I'm studying English.