Absalon-class support ship is the only ship we should consider to replace the LCS.

via Wikipedia.

The Absalon class are support ships of the Royal Danish Navy,[2][3][4] commissioned in 2005. The two ships in the class may be described as an hybrid between a Frigate and military transport ship with multi role capabilities,[5] with the capacity for being transformed from a combat ship with the firepower of a traditional frigate to a hospital ship within a day.[6]

Entry here. 

The Royal Dutch Navy built an LCS Wonder Ship and named it the Absalon Class.  More importantly they got everything that we dreamed of in an affordable package.

Consider this.  When it comes to multi-role weapons it usually doesn't work when it comes to the military.  The exception to the rule is the Absalon Class.

Why the Marine Corps should cheer its purchase is shown in the pics above.  Load one of these puppies up with ACVs, a couple of AH-1Z/UH-1Ys along with mortars, light weight rockets and a couple of MTVRs and you have a pocket MEU that can conduct light amphibious raids.

The Navy would get the Frigate that it always wanted and if the balloon goes up then we have a more capable hospital ship that can maneuver with the fleet instead of hiding hundreds of miles from our battle groups.

The Absalon is ready now.  It can do the job that will take years and millions of dollars to modify the LCS to get done and its relatively cheap.

All we have to do is slay the "not invented here" meme and we can get a ship that is a combat multiplier for everyone from the USN, USMC and even SOCOM.  You want to talk Frigates?  Ok, I raise you the Absalon and dare you to find another that better meets the needs of the force.