there is no lp. as banks are not in the business of transecting crypto. for crypto, brokers are mirroring prices off crypto specific exchanges and making a market for clients. OR they have tied up with an exchange such as gemini to STP your order ...
there is no ecn for crypto(no commission collected on broker side if u pay attention) when you put a order for crypto, the broker is your market maker. so they have the right to manage their risk above your trade as per PDS