Can my current Quarq Elsa for BB30 fit onto/into a 2018 speed concept frame?
You can swap the Elsa spider from your BB30 Quarq onto GXP Quarq or SRAM (removable spider) crankarms. Your Elsa should have 3 torx bolts on the backside. This spider configuration is used for most older Quarqs and SRAM crankarms with removable spiders. Quarq has since moved to an 8 bolt spider pattern.
The GXP setup works well with the SC BB90 bottom bracket standard.
Also rotor and others have bottom brackets to fit a bb30 crankset in a gxp frame.
Haven't seen any offering that would allow 30mm in a BB90 frame. The double row bearings that are available for fitting 30mm crank spindles in 24mm BB's are a litttle too wide for BB90.