I use 30 min. expoxy when I seal crankbaits I've painted, but I don't like the shine it leaves, is there a sealer I can use, where only the color of the bait will show, no sheen on the bait?

I like 'Solarez 71502' for this. It is labeled as a gloss finish, but cures to more of a satin finish. 

It's a UV cure polyester resin, so it will cure completely in only a few minutes with the aid of a UVA lamp. It takes 10-15 minutes to cure completely in direct sunlight if you don't use a lamp. I recommend against curing with the aid of MEK, as this reduces working time. 

I've used this to seal crankbaits and it's tough as nails, and ready to fish in just a few minutes. I also use it to seal balsa baits prior to painting. Great stuff.

On a side note, 30 minute epoxy is really hard to work with for crankbaits. You'd probably fare better with the regular 2-ton epoxy. They both take about the same amount of time to fully cure, but the 2-ton is workable for more than twice as long.

I use Devcon 2 ton epoxy.Great shine an crystal clear.

I use US Composites Kleer Koat .. 2 part epoxy 
http://www.uscomposites.com/epoxy.html

I use both 30min epoxy and solarez and like them both, but as far as the shine of a topcoat goes when the lure is in the water the solarez looks shinny as well

there is another option been hearing about .. its been around awhile ..Its not really something you want to use indoors.. KBS Diamond Clear , its moisture cure urethane .. dip and drip no spinning .. I here others swear that its the best ever.. but its not cheap, and would only advise to use outdoors, or lots of ventilation like open garage and a respirator .

 https://www.kbs-coatings.com/DiamondFinish-Clear.html

I don't know of any real no gloss topcoats but Solarez has the least sheen among the popular choices.  You could probably find a flat auto clear or a clear lacquer if it is critical.

How about buffing down with steel wool?

What about EnviroTex?