If you just dissolve in EtOH then evaporate, final consistency should be almost identical to starting material.
In the case of BHO as crude for distillation, the recommended protocol is to bring up in Ethanol at about 10:1 and throw it in the freezer to ppt the fats and waxes. filter or centrifuge those out, then evaporate/recover ethanol.
That WILL change the consistency. Usually towards a slightly more viscous product.
The next step is to decarboxylate. which can be done at the same time you’re recovering the ethanol. after decarb, the oil is usually considerably less viscous.