I'm not sure there is a way to legally acquire cstrike's server DLL without downloading it from Steam yourself. The Linux counterpart of swds.dll is engine_i486.so, and by the way, Linux counterpart of mp.dll is cs.so.
I could upload it for you, because I have both Linux and Windows on my PC and CS installed on both, but I know I am not allowed to upload binary files, so I'm asking for your permission first.
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